Compositions and methods that enhance an immune response

ABSTRACT

Disclosed herein are isolated nucleic acids, compositions of isolated nucleic acids, and compositions of polypeptides that are useful for the generation, enhancement, or improvement of an immune response to a target antigen. Some embodiments of the compositions include hepatitis B core antigen (HBcAg) protein and a heterologous protein antigen. In some embodiments, an isolated nucleic acid encoding hepatitis B core antigen (HBcAg) protein and a heterologous protein antigen is disclosed. Also disclosed herein are methods of administering the composition or isolated nucleic acid to generate an immune response, where HBcAg acts as adjuvant to improve the immune response to the heterologous protein. In certain embodiments, the HBcAg is as a stork or heron hepatitis antigen.

REFERENCE TO SEQUENCE LISTING

The present application is being filed along with a Sequence Listing inelectronic format. The Sequence Listing is provided as a file entitledTRIPRP116C1SEQLISTING.TXT, created Mar. 28, 2013, which is 360 KB insize. The information in the electronic format of the Sequence Listingis incorporated herein by reference in its entirety.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit and priority to and is a continuingapplication of U.S. application Ser. No. 13/146,755, filed Jul. 28,2011, which is a U.S. National Phase Application of PCT InternationalApplication Number PCT/IB2010/000324, filed on Jan. 29, 2010,designating the United States of America and published in the Englishlanguage, which claims the benefit of priority to U.S. ProvisionalApplication No. 61/292,374, filed Jan. 5, 2010, and U.S. ProvisionalApplication No. 61/149,299, filed Feb. 2, 2009. U.S. application Ser.No. 13/146,755, filed Jul. 28, 2011 is also a continuation-in-part ofInternational Patent Application No. PCT/IB2009/005355, filed Feb. 16,2009, which designated the United States and was published in English.U.S. application Ser. No. 13/146,755, filed Jul. 28, 2011 is also acontinuation-in-part of U.S. patent application Ser. No. 12/371,898,filed Feb. 16, 2009. The disclosures of the above-referenced provisionalapplications and international and domestic patent applications arehereby expressly incorporated by reference in their entireties.

BACKGROUND

Traditionally, vaccines have been based on live attenuated orinactivated pathogens. These strategies are inefficient, however,largely because of the antigenic variability of pathogens (e.g.,viruses). Several peptide vaccines that comprise antigenic peptides orpeptide fragments of pathogens have been developed. Conserved peptidefragments are less likely to exhibit antigenic variability and canovercome some of the problems associated with traditional peptides.Accordingly, subunit vaccines have been developed, which targetconserved regions of pathogens. Synthetic peptide vaccines tend to bepoorly immunogenic, however. The poor immunogenicity of syntheticpeptide vaccines may be attributed to the fact that although these typesof vaccines induce humoral antibody responses, they are less likely toinduce cell-mediated responses.

Several investigators have sought to improve the antigenicity ofsynthetic peptide vaccines. For example, Klein et al. describe theengineering of chimeric proteins that comprise an immunogenic region ofa protein from a first antigen linked to an immunogenic region from asecond pathogen. (See, U.S. Pat. Nos. 6,033,668; 6,017,539; 5,998,169;and 5,968,776). Others have sought to create chimeric proteins thatcouple B-cell epitopes to universal T-cell epitopes in order to improvethe immune response. (See, e.g., U.S. Pat. No. 5,114,713). Russell-Joneset al. (U.S. Pat. No. 5,928,644) also disclose T-cell epitopes derivedfrom the TraT protein of Escherichia coli, which are used to producehybrid molecules so as to generate an immune response to parasites,soluble factors (e.g., LSH) and viruses. Further, Ruslan (U.S. PatentApplication Publication No. 20030232055) discloses the manufacture ofvaccines based on PAMPs and immunogenic antigens.

The hepatitis B virus core antigen (HBcAg) is thought to be a key targetfor the host immune response in the control of the infection. Inparticular, the presence of HBcAg-specific T cells has been associatedwith clearance of acute and chronic infections with the hepatitis Bvirus (HBV). Subsequently, prophylactic and therapeutic vaccines thatinduce HBcAg-specific T cells have been developed and some have shownefficacy in infectious models. However, despite the high immunogenicityof exogenous HBcAg, many of the studies using endogenous HBcAg as avaccine have been disappointing.

When expressed alone, HBcAg will spontaneously assemble into virus-likeparticles (VLPs) that are immunogenic in vivo. These VLPs interact withB cells as the primary antigen-presenting cell (APC) by an unusualinteraction with the B cell receptor. HBcAg effectively primes specificT helper (Th) and, much less effectively, cytotoxic T cells (CTLs) as anexogenous antigen when high antigen doses in adjuvant are used. BothDNA- and retrovirus-based immunizations using HBcAg have been reportedto induce detectable HBcAg-specific CTLs in mice. Some investigatorshave sought to use HBcAg VLPs as a platform to display heterogeneousantigens, as well, but these approaches have been hindered by poorassembly and instability of the particles. (See e.g., U.S. Pat. Nos.4,818,527; 4,882,145; 5,143,726; 6,231,864; 6,887,464; 6,942,866;7,144,712; 7,320,795; 7,351,413; and 7,361,352; the disclosures of whichare hereby expressly incorporated by reference in their entireties).

DNA vaccines can be used as a model to study the endogenousimmunogenicity of antigens. However, phase I/II clinical trials revealthat it is difficult to prime robust immune responses in humans withdirect intramuscular injections of DNA vaccines. Different modes of DNAdelivery have now become available, including transdermal delivery ofDNA coated to gold beads using the gene gun or treatment of theinjection site by in vivo electroporation. The need for approaches thatenhance the immune response of a subject after vaccination, inparticular DNA vaccination, is manifest.

SUMMARY OF THE INVENTION

Several embodiments described herein concern isolated nucleic acids,peptides, compositions and methods that are useful for the generation,enhancement, or improvement of an immune response to a target antigen.These compositions are particularly useful to enhance the immuneresponse of a subject that receives a protein or nucleic acid-basedimmunogen (e.g., DNA immunogen or conventional protein-based vaccine).Although Hepatitis B virus core antigen (HBcAg) is a well known antigen,HBcAg or portions thereof have not been described for use as anadjuvant, which can be administered to a subject in conjunction with aprotein or nucleic acid-based immunogen (e.g., a DNA vaccine) so as toimprove the immune response to the protein or the protein encoded by thenucleic acid immunogen. In a first series of experiments disclosedherein, it was discovered that a nucleic acid encoding HBcAg improvedthe immune response of a subject to a co-administered nucleic acidencoding a hepatitis C virus (HCV) protein (NS3/4A).

In this disclosure, it is revealed that HBcAg, in particular non-humanHBcAgs, such as those derived from an avian hepatitis virus, inparticular, the virus that infects stork and heron, are uniquelysuitable for enhancing an immune response of a subject to aco-administered antigen (e.g., a nucleic acid or peptide immunogen thatis administered in a mixture with the HBcAg adjuvant or withinapproximately at least, equal to, or any number in between 1, 2, 3, 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 30, 45, or 60 minutes beforeor after inoculation with the immunogen). It is contemplated that HBcAgand fragments thereof or a nucleic acid encoding these compositions areuseful additions to immunogen preparations, which improve the immuneresponse of a subject (e.g., a human or mammal) to the immunogen.

Preferably, an HBcAg derived from a hepatitis virus that does not infecta human (a “non-human HBcAg”) or a nucleic acid encoding said non-humanHBcAg is used as the adjuvant (e.g., an HBcAg derived from an avianhepatitis virus, such as the hepatitis virus that infects stork or heron(e.g., SEQ. ID. NOs. 20 and 22). HBV now afflicts almost a third of theworld's population. Accordingly, a significant amount of the populationhas antibodies that react to an HBcAg derived from a hepatitis virusthat infects humans. By utilizing HBcAg sequences derived from divergenthepatitis species, the compositions described herein can be madesuitable for introduction into subjects that are already infected withHBV or subjects that have already generated antibodies to HBV (e.g., asubject that had been previously inoculated with an HBV vaccine).Additionally, when nucleic acids encoding an HBcAg or a fragment thereof(e.g., a nucleic acid encoding an HBcAg derived from an avian hepatitisvirus that infects stork or heron) are administered, these sequencesare, preferably, codon-optimized for expression in the subject (e.g.,codon-optimized for expression in the particular animal or human (e.g.,SEQ. ID. NOs. 20 and 22)).

Accordingly, several aspects of the invention described herein concerncompositions that comprise, consist essentially of, or that consist ofnucleic acids that encode an HBcAg of an avian hepatitis virus (e.g., ahepatitis virus that infects stork or heron (e.g., SEQ. ID. NO. 20 and22)), which has been codon-optimized for expression in humans and, whichcan be joined (e.g., in Cis) to a nucleic acid (preferablycodon-optimized for expression in an animal or human) that encodes aheterologous antigen (e.g., a non-HBV antigen or a non-hepatitisantigen), such as, SEQ. ID. NOs. 2, 8, 10, 12, 14, 16, and 18. In someembodiments, it is preferred that the nucleic acid that encodes aheterologous protein or heterologous protein antigen is inserted in aspike region of the encoded HbcAg (e.g., between amino acid residues ofabout 87 to about 129). Compositions or mixtures that comprise, consistessentially of, or that consist of nucleic acids (e.g., in Trans) thatencode an HBcAg of an avian hepatitis virus (e.g., a hepatitis virusthat infects stork or heron), which has been codon-optimized forexpression in humans (e.g., SEQ. ID. NO. 20 and 22) and a nucleic acid(preferably codon-optimized for expression in an animal or human) thatencodes a heterologous peptide antigen (e.g., a non-HBV peptide or anon-hepatitis peptide), such as SEQ. ID. NOs. 2, 8, 10, 12, 14, 16, and18 are also embodiments. Methods of using the aforementionedcompositions to improve, enhance, or generate an immune response in asubject are also contemplated.

Some embodiments disclosed herein include an immunogenic compositioncomprising an isolated nucleic acid, which is codon optimized forexpression in humans, encoding a hepatitis B virus core antigen (HBcAg)or a fragment thereof that is at least 50 amino acids in length; and anisolated nucleic acid, which is codon optimized for expression inhumans, encoding a heterologous protein antigen. In some embodiments,the HBcAg is a human hepatitis antigen. The HBcAg may, in someembodiments, be a stork hepatitis antigen. In certain embodiments, theHBcAg is a heron hepatitis antigen.

Certain aspects of the immunogenic compositions disclosed hereincomprise a full-length HBcAg. In some embodiments, the immunogeniccomposition comprises a fragment of a HBcAg that is at least 75 aminoacids in length. In some other embodiments, the immunogenic compositioncomprises a fragment of a HBcAg that is at least 125 amino acids inlength. Some embodiments have an immunogenic composition that comprisesa fragment of a HBcAg that is at least 150 amino acids in length. Instill another embodiment, the immunogenic composition comprises afragment of a HBcAg that is at least 175 amino acids in length.

Certain embodiments disclosed herein include an immunogenic compositionwhere the heterologous protein is a viral antigen, plant antigen, oranimal antigen. In some embodiments, the heterologous protein is a viralantigen. Certain aspects of the immunogenic composition include a viralantigen that is a hepatitis antigen. In some embodiments, the hepatitisantigen is a hepatitis C virus (HCV) antigen. In some embodiments, theHCV antigen comprises NS3/4A. In other embodiments, the HCV antigencomprises NS5A. In still other embodiments, the HCV antigen comprisesNS3/4A and NS5A. In some embodiments, the hepatitis antigen comprises ahepatitis B virus (HBV) antigen that is non-naturally occurring or in anon-naturally occurring position with respect to said HBcAg or fragmentthereof. Some embodiments have an HBV antigen that comprises a human HBVsurface antigen, a human HBV e antigen, a human HBcAg, a human HBVpolymerase antigen, or a human HBV x antigen.

In certain aspects, said HBcAg or fragment thereof is a stork or heronhepatitis antigen and said HBV antigen is a human HBcAg. In someaspects, said HBcAg is a stork or heron hepatitis antigen and said HBVantigen is a human HBV e antigen.

In some embodiments, the heterologous protein is a plant antigen. Incertain embodiments, the plant antigen comprises a birch antigen. Insome embodiments, the heterologous protein is an animal antigen. In someaspects, the animal antigen comprises an ovalbumin antigen.

In some embodiments, the immunogenic compositions disclosed hereinincludes said isolated nucleic acid, which is codon optimized forexpression in humans, encodes a full-length HBcAg and said isolatednucleic acid, which is codon optimized for expression in humans, encodesa heterologous protein and both isolated nucleic acids are in the samenucleic acid construct.

Another embodiment includes the immunogenic compositions disclosedherein includes said isolated nucleic acid, which is codon optimized forexpression in humans, encodes a HBcAg and said isolated nucleic acid,which is codon optimized for expression in humans, encodes aheterologous protein and said nucleic acids are in separate nucleic acidconstructs.

In some embodiments of the immunogenic composition, said HBcAg is ahuman hepatitis antigen and said heterologous protein comprises a HCVNS3/4A. In certain aspects,

said immunogenic composition comprises a nucleic acid of sequence SEQ.ID. NO. 10, SEQ. ID. NO. 2, or SEQ. ID. NO. 75.

In some embodiments of the immunogenic composition, said HBcAg is astork hepatitis antigen and said heterologous protein comprises a HCVNS3/4A. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 24, SEQ. ID. NO. 2, or SEQ. ID.NO. 24.

In some embodiments of the immunogenic composition, said HBcAg is aheron hepatitis antigen and said heterologous protein comprises a HCVNS3/4A. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 22, SEQ. ID. NO. 2, or SEQ. ID.NO. 32.

In some embodiments of the immunogenic composition, said HBcAg is ahuman hepatitis antigen and said heterologous protein comprises a HCVNS5A. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 10 or SEQ. ID. NO. 8.

In some embodiments of the immunogenic composition, said HBcAg is astork hepatitis antigen and said heterologous protein comprises a HCVNS5A. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 20, SEQ. ID. NO. 2, or SEQ. ID.NO. 28.

In some embodiments of the immunogenic composition, said HBcAg is aheron hepatitis antigen and said heterologous protein comprises a HCVNS5A. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 22, SEQ. ID. NO. 8, or SEQ. ID.NO. 42.

In some embodiments of the immunogenic composition, HBcAg is a humanhepatitis antigen and said heterologous protein comprises a HBV eantigen. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 10, SEQ. ID. NO. 12, or SEQ. ID.No. 14.

In some embodiments of the immunogenic composition, said HBcAg is astork hepatitis antigen and said heterologous protein comprises a HBV eantigen. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 20, SEQ. ID. NO. 12, SEQ. ID. No.14, SEQ. ID. NO. 44 or SEQ. ID. NO. 46.

In some embodiments of the immunogenic composition, said HBcAg is aheron hepatitis antigen and said heterologous protein comprises a HBV eantigen. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 22, SEQ. ID. NO. 12, SEQ. ID. No.14, SEQ. ID. NO. 48 or SEQ. ID. NO. 50.

In some embodiments of the immunogenic composition, said HBcAg is astork hepatitis antigen and said heterologous protein comprises a HBcAgthat is a human hepatitis antigen. In certain aspects, said immunogeniccomposition comprises a nucleic acid of sequence SEQ. ID. NO. 20, SEQ.ID. NO. 10, or SEQ. ID. NO. 52.

In some embodiments of the immunogenic composition, said HBcAg is aheron hepatitis antigen and said heterologous protein comprises a HBcAgthat is a human hepatitis antigen. In certain aspects, said immunogeniccomposition comprises a nucleic acid of sequence SEQ. ID. NO. 22, SEQ.ID. NO. 10, or SEQ. ID. NO. 54.

In some embodiments of the immunogenic composition, said HBcAg is ahuman hepatitis antigen and said heterologous protein comprises a birchantigen. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 10 or SEQ. ID. NO. 18.

In some embodiments of the immunogenic composition, said HBcAg is astork hepatitis antigen and said heterologous protein comprises a birchantigen. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 20, SEQ. ID. NO. 18, or SEQ. ID.NO. 56.

In some embodiments of the immunogenic composition, said HBcAg is aheron hepatitis antigen and said heterologous protein comprises a birchantigen. In certain aspects, said immunogenic composition comprises anucleic acid of sequence SEQ. ID. NO. 22, SEQ. ID. NO. 18, or SEQ. ID.NO. 58.

In some embodiments of the immunogenic composition, said HBcAg is ahuman hepatitis antigen and said heterologous protein comprises anovalbumin antigen. In certain aspects, said immunogenic compositioncomprises a nucleic acid of sequence SEQ. ID. NO. 10, or SEQ. ID. NO.16.

In some embodiments of the immunogenic composition, said HBcAg is astork hepatitis antigen and said heterologous protein comprises anovalbumin antigen. In certain aspects, said immunogenic compositioncomprises a nucleic acid of sequence SEQ. ID. NO. 22, SEQ. ID. NO. 16,or SEQ. ID. NO. 60.

In some embodiments of the immunogenic composition, said HBcAg is aheron hepatitis antigen and said heterologous protein comprises anovalbumin antigen. In certain aspects, said immunogenic compositioncomprises a nucleic acid of sequence SEQ. ID. NO. 22, SEQ. ID. NO. 16,or SEQ. ID. NO. 62.

In some embodiments of the immunogenic composition, said HBcAg is astork or heron hepatitis antigen and said heterologous protein comprisesHCV NS3/4A and NS5A, and an NS3 protease cleavage site between NS5A andsaid HBcAg.

Some embodiments of the immunogenic composition disclosed hereincomprise an isolated HBcAg that is a stork or heron hepatitis antigen ora fragment thereof that is at least 50 amino acids in length and aheterologous protein, wherein said heterologous protein is in admixturewith said HBcAg and not bound thereto. In some embodiments, the HBcAg isa stork hepatitis antigen. In some embodiments, the HBcAg is a heronhepatitis antigen.

Certain aspects of the immunogenic composition comprises a full-lengthHBcAg. Other aspects of the immunogenic composition comprises a fragmentof a HBcAg that is at least 75 amino acids in length. In someembodiments, the immunogenic composition comprises a fragment of a HBcAgthat is at least 125 amino acids in length. In some embodiments, theimmunogenic composition comprises a fragment of a HBcAg that is at least150 amino acids in length. In some embodiments, the immunogeniccomposition comprises a fragment of a HBcAg that is at least 175 aminoacids in length.

In some embodiments, the heterologous protein is a viral antigen, plantantigen, or animal antigen. In some embodiments, the heterologousprotein is a viral antigen. In some embodiments, the viral antigen is ahepatitis antigen. In certain embodiments, the hepatitis antigen is ahepatitis C virus (HCV) antigen. In still other embodiments, the HCVantigen comprises NS3/4A. In another embodiment, the HCV antigencomprises NS5A. In some embodiments, the HCV antigen comprises NS3/4Aand NS5A. In some embodiments, the hepatitis antigen comprises ahepatitis B virus (HBV) antigen that is non-naturally occurring or in anon-naturally occurring position with respect to said HBcAg or fragmentthereof.

In some aspects, the heterologous protein is a plant antigen. In someembodiments, the plant antigen comprises a birch antigen.

In some embodiments, the heterologous protein is an animal antigen. Inan embodiment, the animal antigen comprises an ovalbumin antigen.

Some embodiments of the immunogenic composition disclosed herein, wherethe HBV antigen comprises a human HBV surface antigen, a human HBV eantigen, a human HBcAg, a human HBV polymerase antigen, or a human HBV xantigen. In some embodiments, said HBcAg or fragment thereof is a storkor heron hepatitis antigen and said HBV antigen is a human HBcAg. Insome embodiments, said HBcAg is a stork or heron hepatitis antigen andsaid HBV antigen is a human HBV e antigen.

Some embodiments of the immunogenic composition of disclosed hereinfurther comprise an isolated nucleic acid encoding a protein selectedfrom the group consisting of interleukin (IL) 2, IL12, IL15, IL21,IL28b, galactose transferase (gal transferase), and a toll-like receptorligand (TLR) or an adjuvant selected from the group consisting of IL2,IL12, IL15, IL21, IL28b, gal transferase, a TLR, ribavirin, alum, CpGs,and an oil.

Some embodiments include an isolated nucleic acid encoding an HBcAgfusion protein comprising an isolated nucleic acid, which is codonoptimized for expression in humans, encoding a hepatitis B virus coreantigen (HBcAg) or a fragment thereof that is at least 50 amino acids inlength joined to an isolated nucleic acid, which is codon optimized forexpression in humans, encoding a heterologous protein.

In some embodiments, the HBcAg is a human hepatitis antigen. In stillanother embodiment, the HBcAg is a stork hepatitis antigen. In someembodiments, the HBcAg is a heron hepatitis antigen.

In some embodiments, the nucleic acid comprises a full-length HBcAg. Inother embodiments, the nucleic acid comprises a fragment of a HBcAg thatis at least 75 amino acids in length. In some embodiments, the nucleicacid comprises a fragment of a HBcAg that is at least 125 amino acids inlength. In some other embodiments, the nucleic acid comprises a fragmentof a HBcAg that is at least 150 amino acids in length. In anotherembodiment, the nucleic acid comprises a fragment of a HBcAg that is atleast 175 amino acids in length.

In certain aspects of the isolated nucleic acid disclosed herein, theheterologous protein is a viral antigen, plant antigen, or animalantigen. In some embodiments, the heterologous protein is a viralantigen. In some embodiments, the viral antigen is a hepatitis antigen.In certain embodiments, the hepatitis antigen is a hepatitis C virus(HCV) antigen. In some embodiments, the HCV antigen comprises NS3/4A. Insome embodiments, the HCV antigen comprises NS5A. In some otherembodiments, the HCV antigen comprises NS3/4A and NS5A. In anembodiment, the hepatitis antigen comprises a hepatitis B virus (HBV)antigen that is non-naturally occurring or in a non-naturally occurringposition with respect to said HBcAg or fragment thereof. In someembodiments, the HBV antigen comprises a human HBV surface antigen, ahuman HBV e antigen, a human HBcAg, a human HBV polymerase antigen, or ahuman HBV x antigen.

In some embodiments, heterologous protein is a plant antigen. In anembodiment, the plant antigen comprises a birch antigen.

In some embodiments, the heterologous protein is an animal antigen. Incertain aspects, the animal antigen comprises an ovalbumin antigen.

In some embodiments, said HBcAg or fragment thereof is a stork or heronhepatitis antigen and said HBV antigen is a human HBcAg. In someembodiments, said HBcAg is a stork or heron hepatitis antigen and saidHBV antigen is a human HBV e antigen.

Some embodiments of isolated nucleic acid include nucleic acid isselected from the group consisting of SEQ. ID. Nos. 24, 26, 28, 30, 32,34, 36, 38, 40, 42, 44, 46, 48, 50, 51, 52, 54, 56, 58, 60, 62, 64, 66,68, 73, 75, 77, 79, 81, 83, 85, 87, 89, 103 and 105.

Some embodiments disclosed herein are proteins encoded by the isolatednucleic acid of disclosed herein.

Certain aspects of the present invention include the use of a nucleicacid, protein, or immunogenic composition disclosed herein to prepare amedicament for generating an immune response in a subject to saidheterologous protein.

Some embodiments disclosed herein are a method of using one or more ofthe compositions disclosed herein to produce an immune response in asubject comprising providing one or more of the compositions disclosedherein; and administering said composition to said subject.

Some embodiments disclosed herein are a method of improving an immuneresponse to a heterologous protein in a subject comprising providing oneor more of the compositions disclosed herein; administering saidcomposition to said subject; and measuring an immune response to saidheterologous protein.

In some embodiments, the methods disclosed herein have said compositionis administered by injection. In some embodiments, said injection isintra muscular, dermal, or subdermal. In some embodiments, the methodfurther comprises providing an electrical stimulation. In certainaspects, said electrical stimulation is electroporation.

In some embodiments, the methods include said isolated nucleic acid thatencodes a full-length HBcAg is provided and the isolated nucleic acidthat encodes a full-length HBcAg is administered separately from theisolated nucleic acid that encodes a heterologous protein. In someembodiments, the methods include said isolated nucleic acid that encodesa full-length HBcAg is administered before said isolated nucleic acidthat encodes a heterologous protein.

Some embodiments of the methods disclosed herein, wherein an isolatednucleic acid that encodes a full-length HBcAg is provided and theisolated nucleic acid that encodes a full-length HBcAg is administeredin admixture with the isolated nucleic acid that encodes a heterologousprotein.

Some embodiments include an immunogenic composition comprising a nucleicacid, which is codon-optimized for expression in humans, encoding ahepatitis B virus core antigen (HBcAg) and a heterologous proteinantigen.

Some embodiments include an immunogenic composition comprising ahepatitis B virus core antigen (HBcAg) protein and a nucleic acid, whichis codon-optimized for expression in humans, encoding heterologousprotein antigen.

In some embodiments, said nucleic acid encoding HBcAg or said HBcAgprotein is derived from stork or heron hepatitis virus.

Some embodiments include a method of promoting an immune response in asubject comprising coadministering a nucleic acid, which iscodon-optimized for expression in humans, encoding a hepatitis B viruscore antigen (HBcAg) and a heterologous protein antigen.

Some embodiments include a method of promoting an immune response in asubject comprising: coadministering a hepatitis B virus core antigen(HBcAg) protein and a nucleic acid, which is codon-optimized forexpression in humans, encoding a heterologous protein antigen

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 (a-i) illustrate constructs encoding HBcAg and HCV NS3/N4A.

FIGS. 2 (a-b) show the results from transcription and translation assayson nucleic acids that encode HBcAg and HCV NS3/N4A. The products wereseparated by gel electrophoresis.

FIGS. 3 (a-e) show the results from an ELISpot assay conducted on HLA-A2transgenic mice, which had been administered nucleic acids that encodeHBcAg and HCV NS3/N4A.

FIGS. 4 (a-e) show the results of an ELISpot assay conducted on HCVNS3/4A+HLA-A2 transgenic mice, which had been administered nucleic acidsthat encode HBcAg and HCV NS3/N4A.

DETAILED DESCRIPTION

It has been discovered that hepatitis B core antigen (HBcAg) is a potentadjuvant that improves the immune response of a subject to aco-administered antigen. Disclosed herein are the results of experimentsthat revealed that a nucleic acid encoding HBcAg improved the immuneresponse of a mammal to a co-administered nucleic acid encoding ahepatitis C virus (HCV) protein (NS3/4A). Accordingly, some embodimentsinclude methods enhancing or improving an immune response of a subject,wherein an HBcAg or a nucleic acid encoding an HBcAg is provided to asubject in a mixture with a peptide immunogen or a nucleic acid encodinga peptide immunogen. In some embodiments, the peptide immunogen ornucleic acid encoding a peptide immunogen is provided in C is with theHBcAg (e.g., a fusion protein encoding HBcAg joined to a desired peptideantigen or a nucleic acid encoding said fusion protein, see for exampleSEQ. ID. Nos 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 51,52, 54, 56, 58, 60, 62, 64, 66, 68 and 73, 75, 77, 79, 81, 83, 85, 87and 89). In other embodiments, the peptide immunogen or nucleic acidencoding a peptide immunogen is provided in Trans with the HBcAg (e.g.,HBcAg or a nucleic acid encoding HBcAg (e.g., SEQ. ID. NO. 10, and 22)is provided in a mixture or co-administered with a desired peptideantigen or a nucleic acid encoding said desired peptide antigen (e.g.,SEQ. ID. NOs. 2, 8, 10, 12, 14, 16, and 18). Preferably, thecompositions described herein comprise, consist essentially of, orconsist of an “avian HBcAg,” that is an HBcAg derived from a hepatitisvirus that infects a bird, such as stork or heron). It is contemplatedthat the use of avian HBcAg in the compositions described herein willallow the formulation of immunogenic compositions that are suitable foradministration to HBV infected individuals or subjects that haveantibodies specific for HBV, since antibodies specific for an HBV thatinfects humans (“human HBV”) generally do not cross-react with the HBVthat infects avian species, such as stork and heron. Additionally, it ispreferred that the nucleic acid sequences used in the compositions andmethods disclosed herein are codon-optimized for expression in thesubject to which the immunogenic compositions are to be administered(e.g., humans).

Accordingly, one or more of the compositions described herein can beused to improve, enhance or generate an immune response in a subject. Bysome approaches, a subject in need of an immune response to a particularantigen is identified. The identification step can be accomplished bydiagnostic approaches or clinical evaluation (e.g., a subject in need ofan immune response to HCV can be identified by diagnostic test orclinical evaluation). Next, one or more of the HBcAg-containingcompositions described herein is provided to the identified subject. Insome embodiments, the composition comprises an HBcAg protein or fragmentthereof that is at least, equal to or any number in between about 20,30, 40, 50, 60, 70, 80, 90, 100, 150, or more amino acids (e.g., HBcAgfrom a hepatitis that infects birds or humans) and an antigen to whichan immune response is desired (e.g., an HCV protein, such as NS3/4A orNS5A). In other embodiments, the composition comprises a nucleic acidthat encodes an HBcAg protein or a fragment thereof that is at least,equal to, or any number in between about 20, 30, 40, 50, 60, 70, 80, 90,100, 200, 250, 300, or more amino acids (e.g., HBcAg from a hepatitisthat infects birds or humans) and a nucleic acid encoding an antigen towhich an immune response is desired (e.g., an HCV protein, such asNS3/4A or NS5A). In more embodiments, the composition comprises an HBcAgprotein or fragment thereof that is at least, equal to or any number inbetween about 20, 30, 40, 50, 60, 70, 80, 90, 100, 150 or more aminoacids (e.g., HBcAg from a hepatitis that infects birds or humans) and anucleic acid encoding an antigen to which an immune response is desired(e.g., an HCV protein, such as NS3/4A or NS5A). In still moreembodiments, the composition comprises a nucleic acid that encodes anHBcAg protein or a fragment thereof that is at least, equal to, or anynumber in between about 20, 30, 40, 50, 60, 70, 80, 90, 100, 150, ormore amino acids (e.g., HBcAg from a hepatitis that infects birds orhumans) and an antigen to which an immune response is desired (e.g., anHCV protein, such as NS3/4A or NS5A). Preferably, the compositionsdescribed above utilize an HBcAg protein or nucleic acid encoding anHBcAg protein that is derived from an avian hepatitis virus, such asstork or heron (e.g., SEQ. ID. NO. 20 and 22). Preferably, the peptideantigens or nucleic acids encoding said peptide antigens are hepatitisantigens, such as HCV antigens (e.g., NS3/4A or NS5A), HBV antigens(e.g., HBV surface antigen, HBV e antigen, human HBcAg, a human HBVpolymerase antigen, a human HBV x antigen) or said peptide antigens ornucleic acids encoding said peptide antigens are birch allergens.Exemplary constructs and nucleic acids encoding preferred antigens,which can be used in one or more of the compositions and methodsdescribed herein are provided in SEQ. ID. NOs. 2, 8, 10, 12, 14, 16, and18. Optionally, any of the aforementioned approaches can further includethe step of measuring the immune response of the subject before, during,and after administration of the immunogenic composition. Suchmeasurements can be made, for example, by diagnostic evaluation of viraltiter in the case of viral disease, clinical evaluation, and scratchtests as are used when evaluating the response to allergens.

Generally, the generation, enhancement, or improvement of an immuneresponse refers to an induction of a humoral (antibody) response and/ora cellular response. Most simply, an increase in the amount ofantigen-specific antibodies (e.g., total IgG) can be seen by utilizingone or more of the embodiments described herein. Enhancement of animmune response also refers to any statistically significant change inthe level of one or more immune cells (T cells, B cells,antigen-presenting cells, dendritic cells and the like) or in theactivity of one or more of these immune cells (cytotoxic T lymphocyte(CTL) activity, helper T lymphocyte (HTL) activity, cytokine secretion,change in profile of cytokine secretion). The skilled artisan willreadily appreciate that several methods for measuring or establishingwhether an immune response is generated, enhanced, or improved areavailable. A variety of methods for detecting the presence and levels ofan immune response are available, for example. (See, e.g., CurrentProtocols in Immunology, Ed: John E. Coligan, et al. (2001) John Wiley &Sons, NY, N.Y.; Current Protocols in Molecular Biology, (2001), GreenePubl. Assoc. Inc. & John Wiley & Sons, NY, N.Y.; Ausubel et al. (2001)Current Protocols in Molecular Biology, Greene Publ. Assoc. Inc. & JohnWiley & Sons, Inc., NY, N.Y.; Sambrook et al. (1989) Molecular Cloning,Second Ed., Cold Spring Harbor Laboratory, Plainview, N.Y.); Maniatis etal. (1982) Molecular Cloning, Cold Spring Harbor Laboratory, Plainview,N.Y.; and elsewhere). Illustrative methods useful in this contextinclude intracellular cytokine staining (ICS), ELISPOT, proliferationassays, cytotoxic T cell assays including chromium release or equivalentassays, and gene expression analysis using any number of polymerasechain reaction (PCR) or RT-PCR based assays. For example, the number ofCD8⁺ T-cells specific for a particular antigen or T-cell epitope (TCE)can be measured by flow cytometry. (See, e.g., Frelin et al. (2004) GeneTherapy 11:522-533). CTL priming can also be measured in vivo by, forexample, a tumor inhibition model, in which the ability of an animal(e.g., mouse) to inhibit growth of tumors derived from tumor cellsengineered to express the antigen of interest. Id.

In some embodiments, generation or enhancement of an immune responsecomprises an increase in target-specific CTL activity of between 1.5 and5 fold in a subject that is provided a composition that comprises thenucleic acids or polypeptides disclosed herein (e.g., in the context ofa HBcAg nucleic acid or polypeptide), wherein the TCE is derived fromthe target, as compared to the same TCE that is not provided in thecontext of the compositions disclosed herein. In some embodiments, anenhancement of an immune response comprises an increase intarget-specific CTL activity of about 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6,6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 15, 16, 17,18, 19, 20, or more fold in a subject that is provided a compositionthat comprises a nucleic acid or a polypeptide disclosed herein (e.g.,in the context of a HBcAg nucleic acid or polypeptide), wherein the TCEis derived from the target, as compared to administration of the sameTCE that is not provided in the context of the compositions disclosedherein.

In other embodiments, an alteration of an immune response comprises anincrease in target-specific HTL activity, such as proliferation ofhelper T cells, of between 1.5 and 5 fold in a subject that is provideda composition that comprises a nucleic acid or polypeptide disclosedherein (e.g., in the context of a HBcAg nucleic acid or polypeptide),wherein the TCE is derived from the target, as compared to the same TCEthat is not provided in the context of the compositions disclosedherein. In some embodiments, alteration of an immune response comprisesan increase in target-specific HTL activity of about 2, 2.5, 3, 3.5, 4,4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12,12.5, 15, 16, 17, 18, 19, 20, or more fold in a subject that is provideda composition that comprises a nucleic acid or polypeptide disclosedherein (e.g., in the context of a HBcAg nucleic acid or polypeptide),wherein the TCE is derived from the target, as compared toadministration of the same TCE that is not provided in the context ofthe compositions disclosed herein. In this context, an enhancement inHTL activity may comprise an increase as described above, or decrease,in production of a particular cytokine, such as interferon-gamma (IFNγ),interleukin-1 (IL-1), IL-2, IL-3, IL-6, IL-7, IL-12, IL-15, tumornecrosis factor-alpha (TNFα), granulocyte macrophage colony-stimulatingfactor (GM-CSF), granulocyte-colony stimulating factor (G-CSF), or othercytokine. In this regard, generation or enhancement of an immuneresponse may comprise a shift from a Th2 type response to a Th1 typeresponse or in certain embodiments a shift from a Th1 type response, toa Th2 type response. In other embodiments, the generation or enhancementof an immune response may comprise the stimulation of a predominantlyTh1 or a Th2 type response.

In still more embodiments, an increase in the amount of antibodyspecific for the antigen (e.g., total IgG) is increased. Someembodiments, for example, generate an increase in heterologoustarget-specific antibody production of between 1.5, 2, 3, 4, or 5 foldin a subject that is provided a composition comprising the nucleic acidsor polypeptides disclosed herein, (e.g., in the context of a HBcAgnucleic acid or polypeptide), wherein the TCE is derived from thetarget, as compared to the same TCE that is not present in the contextof the compositions disclosed herein. In some embodiments, the increasein heterologous target-specific antibody production is about 2, 2.5, 3,3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5,12, 12.5, 15, 16, 17, 18, 19, 20, or more fold in a subject that isprovided a composition that comprises a nucleic acid or polypeptidedisclosed herein, (e.g., in the context of a HBcAg nucleic acid orpolypeptide), wherein the TCE is derived from the target, as compared toas compared to administration of the same TCE that is not present in thecontext of the compositions disclosed herein.

Generation or enhancement of a cellular immune response can also referto the frequency of cytotoxic T lymphocytes (CTLs) specific for adesired antigen that are primed, or the rapidity of priming of cytotoxicT lymphocytes (CTLs) specific for a desired antigen, compared to thepriming of CTLs specific for the desired epitope when the epitope is notpresented in the context of the nucleic acids or peptides disclosedherein. The section below describes several of the HBcAg andheterologous protein sequences that can be used in the compositions andmethods described herein.

Isolated Nucleic Acids and Proteins

Disclosed herein are compositions that comprise isolated nucleic acidsencoding HBcAg, or a fragment thereof, joined to (e.g., flanking orjuxtaposed to) an isolated nucleic acid encoding a heterologous protein.Accordingly, the isolated nucleic acid may, in some embodiments, encodea fusion protein that includes at least a fragment of HBcAg, and aheterologous protein. Polypeptides encoded by said isolated nucleicacids are also embodiments of the present invention.

FIG. 1( a-i) shows various embodiments of constructs that include HBcAgjoined to HCV NS3/4A, which is an exemplary heterologous protein (and anantigen) within the scope of the present invention. FIG. 1 a shows anexemplary construct having HCV NS3/4A joined to HBcAg, which isexemplified by SEQ. ID. No. 22. The sequence includes portions thatencode HCV NS3/4A juxtaposed to HBcAg, and therefore encode a fusionprotein (e.g., SEQ. ID. No. 23 encoded in SEQ. ID. No. 24). Similarly,FIG. 1 b shows another construct having HCV NS3/4A joined to HBcAg,which encodes a mutant NS3 polypeptide and is exemplified by SEQ. ID.No. 26

FIGS. 1( c-i) show various embodiments of constructs that include HBcAgjoined to HCV NS3/4A, where one or more cleavage sites are encodedbetween portions of the polypeptides encoded thereon. FIG. 1( c) encodesan NS3/4A junction between the NS3 and NS4A, and therefore encodes aprotein configured to be cleaved by NS3 protease to provide an NS3polypeptide, and an NS4A-HBcAg fusion protein. SEQ. ID. No. 38 is anexemplary sequence encoding the protein in SEQ. ID. No. 37 and includesthe same features as the construct shown in FIG. 1( c). Furthermore,FIG. 1( d) shows a construct having two cleavage sites, where theconstruct encodes a protein that may be cleaved to form NS3, NS4A andHBcAg polypeptides. SEQ. ID. No. 64 exemplifies a nucleic acid sequencesharing the same features shown in FIG. 1( d). Finally, FIGS. 1( e-i)show embodiments of constructs 5 cleavage sites positioned betweenvarious portions of the encoded polypeptide. These constructs include 3cleavage sites between fragments of HBcAg, and therefore encode apolypeptide configured to be cleaved by NS3 protease to form at least 4fragments of HBcAg. Non-limiting examples of the constructs disclosed inFIGS. 1( e-i) are SEQ. ID. Nos. 81, 83, 85, 87 and 89, respectively.

The nucleocapsid or core antigen HBcAg of HBV is an immunogenic particlecomposed of 180 subunits of a single protein chain. HBcAg has beendisclosed as an immunogenic moiety that stimulates the T cell responseof an immunized host animal. See, e.g, U.S. Pat. No. 4,818,527, U.S.Pat. No. 4,882,145 and U.S. Pat. No. 5,143,726, each of which is herebyincorporated by reference in their entirety. It can be used as a carrierfor several peptidic epitopes covalently linked by genetic engineeringas well as for chemically coupled protein antigens. (See Sällberg et al.(1998) Human Gene Therapy 9:1719-29). In addition, HBcAg isnon-cytotoxic in humans. Accordingly, it was contemplated that HBcAg isuseful in genetic constructs for generating or enhancing an immuneresponse to an accompanied target antigen (e.g., in constructs thatencode a TCE derived from a pathogen).

Current listings of exemplary HBcAg sequences are publicly available atthe National Center for Biotechnology Information (NCBI) world-wide website. HBcAg nucleic acid sequences (including novel HBcAg regions) canalso be isolated from subjects (e.g., humans) infected with HBV. DNAobtained from a patient infected with HBV can be amplified using PCR oranother amplification technique.

For a review of PCR technology, see Molecular Cloning to GeneticEngineering White, B. A. Ed. in Methods in Molecular Biology 67: HumanaPress, Totowa (1997) and the publication entitled “PCR Methods andApplications” (1991, Cold Spring Harbor Laboratory Press). Foramplification of mRNAs, it is within the scope of the invention toreverse transcribe mRNA into cDNA followed by PCR(RT-PCR); or, to use asingle enzyme for both steps as described in U.S. Pat. No. 5,322,770.Another technique involves the use of Reverse Transcriptase AsymmetricGap Ligase Chain Reaction (RT-AGLCR), as described by Marshall R. L. etal. (PCR Methods and Applications 4:80-84, 1994).

The source of the HBcAg sequences that are included in the isolatednucleic acids described herein is not particularly limited. Accordingly,embodiments described herein may utilize an isolated nucleic acid thatencodes an HBcAg derived from a hepatitis virus capable of infectinganimals of any species, including but limited to, humans, non-humanprimates (e.g., baboons, monkeys, and chimpanzees), rodents, mice,reptiles, birds (e.g., stork and heron), pigs, micro-pigs, goats, dogsand cats. In some embodiments, the HBcAg is selected from a humanhepatitis antigen or an avian hepatitis antigen. Particularly preferredare the stork hepatitis antigen and a heron hepatitis antigen.

In certain embodiments, the HBcAg sequences described herein havevariations in nucleotide and/or amino acid sequences, compared to nativeHBcAg sequences and are referred to as HBcAg variants or mutants. Asused herein, the term “native” refers to naturally occurring HBVsequences (e.g., available HBV isotypes). Variants may include asubstitution, deletion, mutation or insertion of one or morenucleotides, amino acids, or codons encoding the HBcAg sequence, whichmay result in a change in the amino acid sequence of the HBcAgpolypeptide, as compared with the native sequence. Variants or mutantscan be engineered, for example, using any of the techniques andguidelines for conservative and non-conservative mutations set forth,for instance, in U.S. Pat. No. 5,364,934, which is hereby incorporatedby reference in its entirety.

Accordingly, when the term “consisting essentially of” is used, in somecontexts, variants or mutants of an HBcAg sequence or of a particularantigen sequence are intended to be encompassed. That is, in somecontexts and in some embodiments, the variants or mutants of thesequences disclosed herein (e.g., SEQ. ID. No. 10) are equivalentsbecause the variation or mutation in sequence does not change ormaterially affect the basic and novel characteristics of the claimedinvention.

A codon-optimized HBcAg can, in some embodiments, be encoded within theisolated nucleic acid. A codon-optimized sequence may, in someembodiments, be obtained by substituting codons in an existing sequencewith codons more frequently used in the intended host subject (e.g., ahuman). Some examples include, but are not limited to, codon-optimizednucleic acids encoding human HBcAg (e.g., SEQ. ID. No. 10),codon-optimized nucleic acids encoding stork HBcAg (e.g., SEQ. ID. No.20), and codon-optimized nucleic acids encoding heron HBcAg (e.g., SEQ.ID. No. 22).

The isolated nucleic acids can encode the full-length HBcAg in certainembodiments (e.g., SEQ. ID. No. 71). However, fragments of the HBcAg mayalso be encoded with the nucleic acid in certain embodiments. A fragmentof the HBcAg sequence can comprise at least, equal to, greater than, orless than, or any number in between 3, 5, 10, 20, 50, 75, 100, 125, 150,or 175 consecutive amino acids of a natural or synthetic HBcAgpolypeptide (e.g., a naturally occurring isotype or a codon-optimized orotherwise modified HBcAg polypeptide). FIGS. 1( e-i) illustrate severalconstructs encoding fragments of HBcAg that are between about 40 toabout 60 amino acids in length.

Some embodiments include, for example, one or more of the HBcAg nucleicacid or protein sequences disclosed in International Patent ApplicationPublication Number WO 20091130588, which designated the United Statesand was published in English, the disclosure of which is herebyexpressly incorporated by reference in its entirety.

Meanwhile, the isolated nucleic acid encoding HBcAg may also be joinedto an isolated nucleic acid encoding a heterologous protein. Theheterologous protein may generally vary in the same manner discussedabove with respect to the HBcAg. Thus, in some embodiments, the isolatednucleic acid sequences may encode native, variants or mutants of aheterologous protein, and these nucleic acids may also becodon-optimized (e.g., a codon-optimized nucleic acid encoding HCVNS3/4A from the human hepatitis virus in SEQ. ID. No. 2, acodon-optimized nucleic acid encoding NS5A from the human hepatitisvirus in SEQ. ID. No. 8, codon-optimized nucleic acid encoding HBV HBcAgfrom the human hepatitis virus in SEQ. ID. No. 10, codon-optimizednucleic acid encoding HBV HBeAg from the human hepatitis virus in SEQ.ID. Nos. 12 and 14, codon-optimized nucleic acid encoding ovalbumin inSEQ. ID. No. 16, codon-optimized nucleic acid encoding birch antigen inSEQ. ID. No. 18). In some embodiments, the isolated nucleic acid encodesa fragment of the heterologous protein. In some embodiments, all of thevaccine sequences include a Kozak sequence (e.g., SEQ. ID. No. 106).

The heterologous protein, in some embodiments, can be an antigen, suchas a plant antigen (e.g., birch antigen), viral antigen, or an animalantigen (e.g., ovalbumin antigen). The antigen may also be a hepatitisantigen, for example a hepatitis B virus (HBV) antigen or a hepatitis Cvirus (HCV) antigen. The HCV antigens can be from viruses known toinfect animals of any species, including, but not limited to,amphibians, reptiles, birds—such as stork, and heron, mice, hamsters,rats, rabbits, guinea pigs, woodchucks, pigs, micro-pigs, goats, dogs,cats, humans and non-human primates (e.g., baboons, monkeys, andchimpanzees). Similarly, the HBV antigens can be from viruses known toinfect animals of any species, including, but not limited to,amphibians, reptiles, birds—such as stork, and heron, mice, rodents,pigs, micro-pigs, goats, dogs, cats, humans and non-human primates(e.g., baboons, monkeys, and chimpanzees). In certain embodiments, theantigen is a HCV antigen selected from NS3/4A, NS5A, and combinationsthereof. In certain embodiments, the antigen is a HBV antigen selectedfrom a HBV surface antigen, HBV e antigen, human HBcAg, a human HBVpolymerase antigen, a human HBV x antigen, and combinations thereof.

If the isolated nucleotide encodes a heterologous protein that is an HBVantigen, the heterologous protein can be substantially different thanthe HBcAg also encoded in the isolated nucleotide. As an example, theisolated nucleic acid may include a nucleic acid encoding HBcAg, whichis joined to an isolated nucleic acid encoding a heterologous protein,where the heterologous protein is an HBV antigen that is non-naturallyoccurring or in a non-naturally occurring position with respect to theHBcAg. SEQ. ID. No. 54 is an exemplary nucleic acid that includes thisfeature because it encodes heron HBcAg joined to human HBcAg. Withoutbeing limited to any particular designation, the human HBcAg is an HBVantigen that is in a non-naturally occurring position with respect tothe heron HBcAg. Conversely, the heron HBcAg may be designated as theHBV antigen that is in a non-naturally occurring position with respectto the human HBcAg.

Some embodiments have an isolated nucleic acid that encodes at least astork or heron HBcAg antigen, or a fragment thereof, and human HBcAg, ora fragment thereof (e.g., SEQ. ID. No. 52 and 54). In certainembodiments, the isolated nucleic acid encodes at least stork or heronHBcAg antigen, or a fragment thereof, and human HBV e antigen, or afragment thereof (e.g., SEQ. ID. 44 and 46).

Some embodiments include, for example, one or more heterologousproteins, or isolated nucleic acids encoding the same, in InternationalPatent Application Publication Number WO 20091130588, which designatedthe United States and was published in English, the disclosure of whichis hereby expressly incorporated by reference in its entirety. As anexample, various HCV HS3/4A polypeptides, and fragments of HCV HS3/4Apolypeptides, are disclosed within WO 20091130588 which may be includedin the isolated nucleic acids.

Non-limiting examples of isolated nucleic acids encoding HBcAg, or afragment thereof, joined to an isolated nucleic acid encoding aheterologous protein, include, but are not limited to: (1) stork HBcAgjoined to HCV NS3/4A (e.g., SEQ. ID. No. 24 and 26); (2) heron HBcAgjoined to HCV NS3/4A (e.g., SEQ. ID. No. 36); (3) stork HBcAg joined toHCV NS5A (e.g., SEQ. ID. No. 40); (4) heron HBcAg joined to HCV NS5A(e.g., SEQ. ID. No. 42); (5) stork HBcAg joined to human HBV e antigen(e.g., SEQ. ID. No. 44 and 46); (6) heron HBcAg joined to human HBV eantigen (e.g., SEQ. ID. No. 48 and 50); (7) stork HBcAg and human HBcAg(e.g., SEQ. ID. No. 52 and 103); (8) heron HBcAg joined to human HBcAg(e.g., SEQ. ID. No. 50 and 105); (9) stork HBcAg joined to birch antigen(e.g., SEQ. ID. No. 56); (10) heron HBcAg joined to birch antigen (e.g.,SEQ. ID. No. 58); (11) stork HBcAg joined to ovalbumin antigen (e.g.,SEQ. ID. No. 60); and (12) stork HBcAg joined to ovalbumin antigen(e.g., SEQ. ID. No. 62).

In some aspects, as discussed above, the isolated nucleic acid includesone or more NS3 protease cleavage sites, wherein the NS3 proteasecleavage site is at a non-naturally occurring position. Examples ofcleavage sites that may be included in the isolated nucleic acidinclude, but are not limited to, SEQ. ID. No. 4 and 6. In certainembodiments, the NS3 protease cleavage site is between the sequencesencoding HBcAg and the heterologous protein. Thus, in some embodiments,the isolated nucleic acids encode a fusion protein, which may be cleavedby NS3 protease. In other aspects, the isolated nucleic acid encodes twoor more fragments of HBcAg having a cleavage site between the twoencoded fragments. Accordingly, the isolated nucleic acid encodingfragments of HBcAg, and therefore encodes a protein that is configuredto be cleaved by NS3 protease to form HBcAg fragments.

Some embodiments of the isolated nucleic acid include an isolatednucleic acid encoding HBcAg, or a fragment thereof, joined to anisolated nucleic acid encoding heterologous protein, wherein theheterologous protein is HCV NS3/4A (e.g., SEQ. ID. No. 24). In certainembodiments, the isolated nucleic acid encodes an NS3 protease cleavagesite between the isolated nucleic acid encoding HCV NS3/4A and theisolated nucleic acid encoding HBcAg (e.g., SEQ. ID. No. 30).

Embodiments of the isolated nucleic acid include HBcAg and a pluralityof isolated nucleic acids encoding antigens, each of the isolatednucleic acids being joined together and having an HCV protease cleavagesite in between. As an example, SEQ. ID. Nos. 64, 66, and 68 includeNS3/4A antigen, NS5A antigen, and HBcAg antigen having an HCV proteasecleavage site between each antigen.

Some embodiments of the isolated nucleic acids disclosed herein encode afragment of human HBcAg between (i.e., joined at both ends to) fragmentsof avian HBcAg (e.g., stork or heron HBcAg). Thus, for example, theisolated nucleic acid may encode a polypeptide, where the polypeptidecomprises, consists essentially of, or consists of avian HBcAg having afragment of human HBcAg inserted into said avian HBcAg. In some aspects,the human HBcAg fragment is inserted into at least a portion, or all, ofthe spike region of the avian HBcAg (i.e., the region of HBcAg displayedon the surface the HBcAg capsid). Preferably, the human HBcAg is encodedinto any, or all, of the amino acid positions 87 to 129 in the nucleicacid encoding avian HBcAg (e.g., codon-optimized stork HBcAg (e.g., SEQ.ID. No. 20) or codon-optimized heron HBcAg (e.g., SEQ. ID. No. 22)). Ina preferred embodiment, the isolated nucleic acid encodes about a 43amino acid fragment of human HBcAg inserted into amino acid positions ofabout 87 to about 129 of an avian HBcAg (e.g., an isolated nucleic acidthat encodes codon-optimized stork HBcAg having 43 amino acid fragmentof human HBcAg inserted at amino acid positions 87 to 129 (e.g., SEQ.ID. No. 103, which encodes the fusion protein in SEQ. ID. No. 102), oran isolated nucleic acid that encodes codon-optimized heron HBcAg havinga 43 amino acid fragment of human HBcAg is inserted at amino acidpositions 87 to 129 (e.g., SEQ. ID. No. 105, which encodes the fusionprotein in SEQ. ID. No. 104)).

As would be appreciated by a person of ordinary skill, the proteinsencoded in the isolated nucleic acids disclosed herein may be obtainedusing known methods. As an example, the nucleic acids may be insertedinto an appropriate plasmid, which is subsequently inserted into tocells that express the protein. Other methods for obtaining the encodedproteins are also known. Accordingly, the scope of the presentapplication includes the proteins that can be obtained from the isolatednucleic acids disclosed herein. For example, SEQ. ID. 23 describes aprotein that can be obtained from the expression of SEQ. ID. 24. Thus,embodiments of the present invention also include, but are not limitedto, proteins having the sequences in SEQ. ID. Nos. 23, 25, 27, 29, 31,33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67,69, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 102 and 104.

Immunogenic Compositions Comprising Nucleic Acids

Disclosed herein are immunogenic compositions relating to geneticconstructs that include nucleic acids encoding HBcAg, or a fragmentthereof, and nucleic acids encoding a heterologous protein. In someembodiments, both sequences are in the same nucleic acid construct(e.g., the same plasmid). In certain embodiments, both sequences are inseparate nucleic acid constructs. Some embodiments of the immunogeniccompositions described herein include any of the isolated nucleic acidsdiscussed above, wherein a nucleic acid encoding HBcAg, or a fragmentthereof, is joined to a nucleic acid encoding a heterologous protein.Some embodiments of the immunogenic compositions disclosed hereininclude one or proteins encoded by a nucleic acid described herein.

The source of the HBcAg that is encoded in the nucleic acid is notparticularly limited. Accordingly, the nucleic acid contemplated for theimmunogenic compositions described herein can be nucleic acids fromviruses known to infect animals of any species, including but limitedto, humans, mice, reptiles, birds (e.g., stork and heron), rodents,pigs, micro-pigs, goats, dogs, cats, and non-human primates (e.g.,baboons, monkeys, and chimpanzees), as mentioned above. In someembodiments, the HBcAg is selected from a human hepatitis antigen, anavian hepatitis antigen, a stork hepatitis antigen, and a heronhepatitis antigen.

The sequences encoding HBcAg can generally be the same as thosediscussed above with respect to the isolated nucleic acids. Thus, insome embodiments, any of the nucleic acid sequences described above thatinclude HBcAg may be used in the immunogenic composition. As an example,the isolated nucleic acid may include native (e.g., SEQ. ID. No. 71) orvariant HBcAg or mutant HBcAg, and the nucleic acid may also becodon-optimized (e.g., SEQ. ID. No. 22). In some embodiments, theisolated nucleic acid encodes a fragment of HBcAg, as described abovewith respect to the isolated nucleic acids. For example, fragment of theHBcAg sequence can comprise at least, equal to, greater than, or lessthan, or any number in between 3, 5, 10, 20, 50, 75, 100, 125, 150, or175 consecutive amino acids of a natural or synthetic HBcAg polypeptide.A full-length HBcAg can also be encoded in an isolated nucleic acidincluded within the immunogenic composition.

Some embodiments include nucleic acids that have homology or sequenceidentity to any one of the nucleic acid sequences disclosed herein (e.g.SEQ. ID. Nos. 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50,52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 102, 104 etc.). In someembodiments, said homologous nucleic acids generate, enhance, or improvean immune response, as defined above. Several techniques exist todetermine nucleic acid or protein sequence homology. Thus, embodimentsof the nucleic acids can have from 70% homology or sequence identity to100% homology or sequence identity to any one of the nucleic acidsequences or protein sequences disclosed herein. That is, embodimentscan have at least, equal to or any number between about 70.0%, 71.0%,72.0%, 73.0%, 74.0%, 75.0%, 76.0%, 77.0%, 78.0%, 79.0%, 80.0%, 81.0%,82.0%, 83.0%, 84.0%, 85.0%, 86.0%, 87.0%, 88.0%, 89.0%, 90.0%, 91.0%,92.0%, 93.0%, 94.0%, 95.0%, 96.0%, 97.0%, 98.0%, 99.0%, and 100.0%homology or sequence identity to any one of the polypeptide or nucleicacid sequences disclosed herein.

Several homology or sequence identity searching programs based onnucleic acid sequences are known in the art and can be used to identifymolecules that are homologous. In one approach, a percent sequenceidentity can be determined by standard methods that are commonly used tocompare the similarity and position of the base pairs of two nucleicacids. Using a computer program such as BLAST or FASTA, two sequencescan be aligned for optimal matching of their respective base pairs(either along the full length of one or both sequences, or along apredetermined portion of one or both sequences). Such programs provide“default” opening penalty and a “default” gap penalty, and a scoringmatrix such as PAM 250 (a standard scoring matrix; see Dayhoff et al.,in: Atlas of Protein Sequence and Structure, Vol. 5, Supp. 3 (1978)) canbe used in conjunction with the computer program.

Some embodiments included isolated nucleic acids having sufficienthomology or sequence identity to any one of the nucleic acid sequencesdisclosed herein such that hybridization will occur between the isolatednucleic acid and any one of the nucleic acids sequences disclosedherein. In some aspects, hybridization occurs under usual washingconditions in Southern hybridization, that is, at a salt concentrationcorresponding to 0.1 times saline sodium citrate (SSC) and 0.1% SDS at37° C. (low stringency), preferably 0.1 times SSC and 0.1% SDS at 60° C.(medium stringency), and more preferably 0.1 times SSC and 0.1% SDS at65° C. (high stringency). In certain aspects, the nucleic acidembodiments have a percentage of consecutive bases that hybridize understringent conditions with any one of the nucleic acids sequencesdisclosed herein, where the number of consecutive bases is at least40.0%, 41.0%, 42.0%, 43.0%, 44.0%, 45.0%, 46.0%, 47.0%, 48.0%, 49.0%,50.0%, 51.0%, 52.0%, 53.0%, 54.0%, 55.0%, 56.0%, 57.0%, 58.0%, 59.0%,60.0%, 61.0%, 62.0%, 63.0%, 64.0%, 65.0%, 66.0%, 67.0%, 68.0%, 69.0%,70.0%, 71.0%, 72.0%, 73.0%, 74.0%, 75.0%, 76.0%, 77.0%, 78.0%, 79.0%,80.0%, 81.0%, 82.0%, 83.0%, 84.0%, 85.0%, 86.0%, 87.0%, 88.0%, 89.0%,90.0%, 91.0%, 92.0%, 93.0%, 94.0%, 95.0%, 96.0%, 97.0%, 98.0%, 99.0%,and 100.0% of the total number of bases in the nucleic acid sequence.

Some embodiments of the immunogenic composition include a nucleic acidencoding a heterologous protein. The heterologous protein encoded by thenucleic acid, in some embodiments, can be an antigen, such as a plantantigen (e.g., birch antigen), viral antigen, or an animal antigen(e.g., ovalbumin antigen). The antigen may also be a hepatitis antigen,for example a hepatitis B virus (HBV) antigen or a hepatitis C virus(HCV) antigen. The HCV antigens can be from viruses known to infectanimals of any species, including, but not limited to, amphibians,reptiles, birds (e.g., stork and heron) mice, hamsters, rats, rabbits,guinea pigs, woodchucks, pigs, micro-pigs, goats, dogs, cats, humans andnon-human primates (e.g., baboons, monkeys, and chimpanzees). Similarly,the HBV antigens can be from viruses known to infect animals of anyspecies, including, but not limited to, amphibians, reptiles, birds(e.g., stork and heron), and heron, mice, hamsters, rodents, pigs,micro-pigs, goats, dogs, cats, humans and non-human primates (e.g.,baboons, monkeys, and chimpanzees). In certain embodiments, the antigenis a HCV antigen selected from NS3/4A, NS5A, and combinations thereof.In certain embodiments, the antigen is a HBV antigen selected from a HBVsurface antigen, HBV e antigen, human HBcAg, a human HBV polymeraseantigen, a human HBV x antigen, and combinations thereof.

Non-limiting examples of nucleic acids encoding heterologous proteinsthat may be included within the immunogenic composition include HCVNS3/4A (e.g., SEQ. ID. 2), HCV NS5A (e.g., SEQ. ID. 8), HBcAg (e.g.,SEQ. ID. 10), HBV e antigen (e.g., SEQ. ID. 12 and 14), and ovalbumin(e.g., SEQ. ID. 16).

If the immunogenic composition includes an encoded heterologous proteinthat is an HBV antigen, the heterologous protein or nucleic acidencoding the heterologous protein can be substantially different thanthe HBcAg present in the immunogenic composition. As example, theimmunogenic composition may include a nucleic acid encoding HBcAg, and anucleic acid encoding a heterologous protein, which is an HBV antigenthat is non-naturally occurring or in a non-naturally occurring positionwith respect to the HBcAg. The immunogenic composition may include, forexample, a mixture of SEQ. ID. No. 10 and 22, and therefore includes twonucleic acids encoding substantially different HBV antigens (i.e., humanHBcAg and heron HBcAg).

Non-limiting examples of mixtures of nucleic acid sequences encodingHBcAg, or a fragment thereof, and nucleic acid sequences encoding aheterologous protein, that may be included in the immunogeniccompositions, include, but are not limited to, nucleic acid sequencesencoding: (1) stork HBcAg and HCV NS3/4A (e.g., SEQ. ID. Nos. 20 and 2);(2) heron HBcAg and HCV NS3/4A (e.g., SEQ. ID. Nos. 22 and 2); (3) storkHBcAg and HCV NS5A (e.g., SEQ. ID. Nos. 20 and 8); (4) heron HBcAg andHCV NS5A (e.g., SEQ. ID. Nos. 22 and 8); (5) stork HBcAg and human HBV eantigen (e.g., SEQ. ID. Nos. 20 and 12); (6) heron HBcAg and human HBV eantigen (e.g., SEQ. ID. Nos. 22 and 12); (7) stork HBcAg and human HBcAg(e.g., SEQ. ID. Nos. 20 and 10); (8) heron HBcAg and human HBcAg (e.g.,SEQ. ID. Nos. 22 and 10); (9) stork HBcAg and birch antigen (e.g., SEQ.ID. Nos. 20 and 18); (10) heron HBcAg and birch antigen (e.g., SEQ. ID.Nos. 22 and 18); (11) stork HBcAg and ovalbumin antigen (e.g., SEQ. ID.Nos. 20 and 16); and (12) stork HBcAg and ovalbumin antigen (e.g., SEQ.ID. Nos. 22 and 16).

Some embodiments of the immunogenic composition include the isolatednucleic acids described above, wherein the nucleic acid encoding HBcAg,or a fragment thereof, is joined to nucleic acid sequences encoding aheterologous protein. Accordingly, further exemplary compositions mayinclude a nucleic acid encoding: (1) stork HBcAg joined to HCV NS3/4A(e.g., SEQ. ID. No. 24 and 26); (2) heron HBcAg joined to HCV NS3/4A(e.g., SEQ. ID. No. 36); (3) stork HBcAg joined to HCV NS5A (e.g., SEQ.ID. No. 40); (4) heron HBcAg joined to HCV NS5A (e.g., SEQ. ID. No. 42);(5) stork HBcAg joined to human HBV e antigen (e.g., SEQ. ID. No. 44 and46); (6) heron HBcAg joined to human HBV e antigen (e.g., SEQ. ID. No.48 and 50); (7) stork HBcAg joined to human HBcAg (e.g., SEQ. ID. No. 52and 103); (8) heron HBcAg joined to human HBcAg (e.g., SEQ. ID. No. 50and 105); (9) stork HBcAg joined to birch antigen (e.g., SEQ. ID. No.56); (10) heron HBcAg joined to birch antigen (e.g., SEQ. ID. No. 58);(11) stork HBcAg joined to ovalbumin antigen (e.g., SEQ. ID. No. 60);and (12) stork HBcAg joined to ovalbumin antigen (e.g., SEQ. ID. No.62).

It is contemplated that various other compounds may be included in oneor more of the compositions. Some embodiments of the composition mayfurther include an additional adjuvant. Non-limiting example ofadjuvants that can be included are: interleukin-2 (IL2), interleukin-12(IL12), interleukin-15 (IL15), interleukin-21 (IL21), interleukin-28b(IL28b), galactosyl transferase, a toll-like receptor (TLR), ribavirin,alum, CpGs, or an oil. In some embodiments, the composition includes anisolated nucleic acid, or constructs comprising said nucleic acids,encoding a protein that is an adjuvant, such as IL2, IL12, IL15, IL21,IL28b, galactose transferase, a TLR, and the like. In certain aspects,the isolated nucleic acid encoding the protein which is an adjuvant maybe in the same construct encoding HBcAg and/or the heterologous protein.In other aspects, the isolated nucleic acid encoding the protein, whichis an adjuvant may be in a different construct than the constructencoding HBcAg and/or the heterologous protein.

The compositions described herein may also contain other ingredients orcompounds in addition to nucleic acids and/or polypeptides, including,but not limited to, various other peptides, adjuvants, binding agents,excipients such as stabilizers (to promote long term storage),emulsifiers, thickening agents, salts, preservatives, solvents,dispersion media, coatings, antibacterial and antifungal agents,isotonic and absorption delaying agents and the like. See e.g., U.S.application Ser. No. 09/929,955 and U.S. application Ser. No.09/930,591. These compositions are suitable for treatment of animals,particularly mammals, either as a preventive measure to avoid a diseaseor condition or as a therapeutic to treat animals already afflicted witha disease or condition.

Many other ingredients may also be present in the compositions providedherein. For example, the adjuvant and antigen can be employed inadmixture with conventional excipients (e.g., pharmaceuticallyacceptable organic or inorganic carrier substances suitable forparenteral, enteral (e.g., oral) or topical application that do notdeleteriously react with the therapeutic ingredients (e.g., constructencoding HBcAg). Suitable pharmaceutically acceptable carriers include,but are not limited to, water, salt solutions, alcohols, gum arabic,vegetable oils, benzyl alcohols, polyethylene glycols, gelatin,carbohydrates such as lactose, amylose or starch, magnesium stearate,talc, silicic acid, viscous paraffin, perfume oil, fatty acidmonoglycerides and diglycerides, pentaerythritol fatty acid esters,hydroxy methylcellulose, polyvinyl pyrrolidone, etc. Many more suitablecarriers are described in Remmington's Pharmaceutical Sciences, 15thEdition, Easton:Mack Publishing Company, pages 1405-1412 and 1461-1487(1975) and The National Formulary XIV, 14th Edition, Washington,American Pharmaceutical Association (1975).

Immunogenic Compositions Comprising Polypeptides

Some of the embodiments described herein concern compositions thatcomprise, consist essentially of, or consist of polypeptides encoded byany of the nucleic acids disclosed herein. In some embodiments, thecomposition includes an admixture of HBcAg, or a fragment thereof, and aheterologous protein. In certain aspects, the composition includes aprotein having HBcAg joined to a heterologous protein.

The HBcAg polypeptides that may be included in the immunogeniccompositions can be any HBcAg polypeptide that can be encoded in thenucleic acids within the immunogenic composition of nucleic acidsdiscussed above, or those encoded in the isolated nucleic acidsdiscussed above. Thus, in some embodiments, the HBcAg is derived from acodon-optimized nucleic acid (e.g., SEQ. ID. No. 21 is derived from SEQ.ID. No. 22). The HBcAg may also be a native or variant form of theprotein. Also, the composition may include a fragment of HBcAg. Afragment of HBcAg can comprise at least, equal to, greater than, or lessthan, or any number in between 3, 5, 10, 20, 50, 75, 100, 125, 150, or175 consecutive amino acids of a natural or synthetic HBcAg polypeptide(e.g., a naturally occurring isotype or a codon-optimized or otherwisemodified HBcAg polypeptide).

Some embodiments include polypeptides that have homology or sequenceidentity to any one of the polypeptide sequences disclosed herein (e.g.SEQ. ID. Nos. 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49,51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 70, 102, 104, etc.). In someembodiments, said polypeptides generate, enhance, or improve an immuneresponse, as defined above. Several techniques exist to determineprotein sequence homology or sequence identity. Thus, embodiments of thepolypeptides can have from 70% homology to 100% homology or sequenceidentity to any one of the polypeptides disclosed herein. That is,embodiments can have at least, equal to, or any number in between about70.0%, 71.0%, 72.0%, 73.0%, 74.0%, 75.0%, 76.0%, 77.0%, 78.0%, 79.0%,80.0%, 81.0%, 82.0%, 83.0%, 84.0%, 85.0%, 86.0%, 87.0%, 88.0%, 89.0%,90.0%, 91.0%, 92.0%, 93.0%, 94.0%, 95.0%, 96.0%, 97.0%, 98.0%, 99.0%,and 100.0% homology or sequence identity to any one of the polypeptideor nucleic acid sequences disclosed herein.

Several homology or sequence identity searching programs based onpolypeptide sequences are known in the art and can be used to identifymolecules that are homologous. In one approach, a percent sequenceidentity can be determined by standard methods that are commonly used tocompare the similarity and position of the amino acids of twopolypeptides. Using a computer program such as BLAST or FASTA, twosequences can be aligned for optimal matching of their respective aminoacids (either along the full length of one or both sequences, or along apredetermined portion of one or both sequences). Such programs provide“default” opening penalty and a “default” gap penalty, and a scoringmatrix such as PAM 250 (a standard scoring matrix; see Dayhoff et al.,in: Atlas of Protein Sequence and Structure, Vol. 5, Supp. 3 (1978)) canbe used in conjunction with the computer program.

Similarly, the heterologous protein that may be included in theimmunogenic compositions can be any heterologous protein that can beencoded in the nucleic acids within the immunogenic composition ofnucleic acids discussed above, or those encoded in the isolated nucleicacids discussed above. Thus, in some embodiments, the heterologousprotein is derived from a codon-optimized nucleic acid (e.g., SEQ. ID.No. 7 is derived from SEQ. ID. No. 8). The HBcAg may also be a native orvariant form of the protein.

If the immunogenic composition includes a heterologous protein that isan HBV antigen, the heterologous protein can be substantially differentthan the HBcAg present in the immunogenic composition. As example, theimmunogenic composition may include HBcAg, and a heterologous proteinwhich is an HBV antigen that is non-naturally occurring or in anon-naturally occurring position with respect to the HBcAg. Theimmunogenic composition may include, for example, a mixture of SEQ. ID.No. 9 and 11, and therefore includes different HBV antigens (i.e., humanHBcAg and heron HBcAg).

Non-limiting examples of admixtures of HBcAg, or a fragment thereof, anda heterologous protein, which may be included in the immunogeniccompositions, include, but are not limited to: (1) stork HBcAg and HCVNS3/4A (e.g., SEQ. ID. Nos. 19 and 1); (2) heron HBcAg and HCV NS3/4A(e.g., SEQ. ID. Nos. 21 and 1); (3) stork HBcAg and HCV NS5A (e.g., SEQ.ID. Nos. 19 and 7); (4) heron HBcAg and HCV NS5A (e.g., SEQ. ID. Nos. 21and 7); (5) stork HBcAg and human HBV e antigen (e.g., SEQ. ID. Nos. 19and 11); (6) heron HBcAg and human HBV e antigen (e.g., SEQ. ID. Nos. 21and 11); (7) stork HBcAg and human HBcAg (e.g., SEQ. ID. Nos. 19 and 9);(8) heron HBcAg and human HBcAg (e.g., SEQ. ID. Nos. 21 and 9); (9)stork HBcAg and birch antigen (e.g., SEQ. ID. Nos. 19 and 17); (10)heron HBcAg and birch antigen (e.g., SEQ. ID. Nos. 21 and 17); (11)stork HBcAg and ovalbumin antigen (e.g., SEQ. ID. Nos. 19 and 15); and(12) stork HBcAg and ovalbumin antigen (e.g., SEQ. ID. Nos. 21 and 15).

It is also contemplated that some immunogenic compositions can compriseboth a protein as described herein and a nucleic acid as describedherein. For example, some embodiments may include a nucleic acidencoding an HBcAg (e.g., a nucleic acid encoding a stork or heron HBcAg(e.g., SEQ. ID. No. 20 and 22) and a protein that is an antigen (e.g.,HCV NS3/4A SEQ. ID. No. 1). Alternatively, some embodiments areimmunogenic compositions that comprise an HBcAg protein (e.g., stork orheron HBcAg SEQ. ID. No. 19 and 21) and a nucleic acid encoding anantigen (e.g., a nucleic acid encoding HCV NS3/4A SEQ. ID. No. 2).

It is also contemplated that various other ingredients may be includedto improve the immunogenic composition by, for example, increasing theimmune response caused by the composition. Some embodiments of thecomposition may further include an adjuvant. Non-limiting example ofadjuvants include interleukin-2 (IL2), interleukin-12 (IL12),interleukin-15 (IL15), interleukin-21 (IL21), interleukin-28b (IL28b),galactosyl transferase, a toll-like receptor (TLR), ribavirin, alum,CpGs, and an oil.

Various ingredients, such as excipients, adjuvants, binding agents,etc., may be included in the immunogenic compositions including apolypeptide. The same ingredients as those disclose above with respectto immunogenic compositions of isolated nucleic acids may be utilized.

Methods of Enhancing or Promoting an Immune Response

Methods of enhancing or promoting an immune response in an animal,including humans, to an antigen are also provided. Such methods can bepracticed, for example, by identifying an animal in need of an immuneresponse and administering said animal with any of the immunogeniccompositions described above that is effective to enhance or facilitatean immune response to the heterologous protein. In some embodiments,compositions including one or more isolated nucleic acids encoding theHBcAg antigen, or a fragment thereof, and a nucleic acid encoding aheterologous protein are administered to a animal in need thereof at thesame time in the same mixture. In certain embodiments, compositions ofHBcAg antigen, or a fragment thereof, and a heterologous protein areadministered to the animal at the same time in the same mixture.Alternatively, the nucleic acid encoding the HBcAg and the nucleic acidencoding the heterologous protein are coadministered. Similarly, theHBcAg protein and the protein antigen can be coadministered. Bycoadministered, it is mean that the two nucleic acids or two protein areprovided at the same time in the same mixture or within at least, equalto, or about any number in between 1, 5, 10, 15, 20, 30, 40, 50, or 60minutes each separate administration. However, the present invention isnot limited to any particular order of administration.

Accordingly, some methods include administering a composition comprisingan isolated nucleic acid encoding HBcAg, or a fragment thereof, joinedto an isolated nucleic acid encoding a heterologous protein.Non-limiting examples of compositions that may be administered accordingto the methods disclosed herein include, but are not limited t nucleicacids encoding: (1) stork HBcAg joined to HCV NS3/4A (e.g., SEQ. ID. No.24 and 26); (2) heron HBcAg joined to HCV NS3/4A (e.g., SEQ. ID. No.36); (3) stork HBcAg joined to HCV NS5A (e.g., SEQ. ID. No. 40); (4)heron HBcAg joined to HCV NS5A (e.g., SEQ. ID. No. 42); (5) stork HBcAgjoined to human HBV e antigen (e.g., SEQ. ID. No. 44 and 46); (6) heronHBcAg joined to human HBV e antigen (e.g., SEQ. ID. No. 48 and 50); (7)stork HBcAg and human HBcAg (e.g., SEQ. ID. No. 52 and 103); (8) heronHBcAg joined to human HBcAg (e.g., SEQ. ID. No. 50 and 105); (9) storkHBcAg joined to birch antigen (e.g., SEQ. ID. No. 56); (10) heron HBcAgjoined to birch antigen (e.g., SEQ. ID. No. 58); (11) stork HBcAg joinedto ovalbumin antigen (e.g., SEQ. ID. No. 60); and (12) stork HBcAgjoined to ovalbumin antigen (e.g., SEQ. ID. No. 62).

Furthermore, compositions including nucleic acid sequences encodingHBcAg, or a fragment thereof, and nucleic acid sequences encoding aheterologous protein in Trans, may be administered according to themethods disclosed herein. Non-limiting examples of compositions foradministering according to the methods disclosed herein, include, butare not limited to nucleic acids encoding: (1) stork HBcAg and HCVNS3/4A (e.g., SEQ. ID. Nos. 20 and 2); (2) heron HBcAg and HCV NS3/4A(e.g., SEQ. ID. Nos. 22 and 2); (3) stork HBcAg and HCV NS5A (e.g., SEQ.ID. Nos. 20 and 8); (4) heron HBcAg and HCV NS5A (e.g., SEQ. ID. Nos. 22and 8); (5) stork HBcAg and human HBV e antigen (e.g., SEQ. ID. Nos. 20and 12); (6) heron HBcAg and human HBV e antigen (e.g., SEQ. ID. Nos. 22and 12); (7) stork HBcAg and human HBcAg (e.g., SEQ. ID. Nos. 20 and10); (8) heron HBcAg and human HBcAg (e.g., SEQ. ID. Nos. 22 and 10);(9) stork HBcAg and birch antigen (e.g., SEQ. ID. Nos. 20 and 18); (10)heron HBcAg and birch antigen (e.g., SEQ. ID. Nos. 22 and 18); (11)stork HBcAg and ovalbumin antigen (e.g., SEQ. ID. Nos. 20 and 16); and(12) stork HBcAg and ovalbumin antigen (e.g., SEQ. ID. Nos. 22 and 16).

In addition, compositions including HBcAg, or a fragment thereof, and aheterologous protein, may be administered according to the methodsdisclosed herein. Non-limiting examples of the compositions foradministering according to the methods disclosed herein, include, butare not limited to: (1) stork HBcAg and HCV NS3/4A (e.g., SEQ. ID. Nos.19 and 1); (2) heron HBcAg and HCV NS3/4A (e.g., SEQ. ID. Nos. 21 and1); (3) stork HBcAg and HCV NS5A (e.g., SEQ. ID. Nos. 19 and 7); (4)heron HBcAg and HCV NS5A (e.g., SEQ. ID. Nos. 21 and 7); (5) stork HBcAgand human HBV e antigen (e.g., SEQ. ID. Nos. 19 and 11); (6) heron HBcAgand human HBV e antigen (e.g., SEQ. ID. Nos. 21 and 11); (7) stork HBcAgand human HBcAg (e.g., SEQ. ID. Nos. 19 and 9); (8) heron HBcAg andhuman HBcAg (e.g., SEQ. ID. Nos. 21 and 9); (9) stork HBcAg and birchantigen (e.g., SEQ. ID. Nos. 19 and 17); (10) heron HBcAg and birchantigen (e.g., SEQ. ID. Nos. 21 and 17); (11) stork HBcAg and ovalbuminantigen (e.g., SEQ. ID. Nos. 19 and 15); and (12) stork HBcAg andovalbumin antigen (e.g., SEQ. ID. Nos. 21 and 15).

Other embodiments concern methods of inhibiting HCV infection, reducingHCV viral titer, inhibiting HCV replication, treating HCV infection orpromoting an immune response specific for an HCV protein. By oneapproach, an immunogenic composition comprising an isolated nucleic acidencoding HBcAg, or a fragment thereof (e.g., a human codon-optimizednucleic acid encoding a HBcAg derived from an avian hepatitis, such as ahepatitis that infects stork (e.g., SEQ. ID. No. 20) or heron (e.g.,SEQ. ID. No. 22)) and an isolated nucleic acid encoding an HCV antigendescribed herein (e.g., a human codon-optimized nucleic acid encodingNS3, NS3/4A (e.g., SEQ. ID. No. 2), and/or NS5A (e.g., SEQ. ID. 8) areused to prepare a medicament for the inhibition of HCV infection, thereduction of HCV viral titer, the inhibition of HCV replication, thetreatment of HCV infection or for the generation of an immune responseto an HCV protein. That is, preferred compositions comprise, consistessentially of, or consist of a nucleic acid encoding HBcAg derived froman avian hepatitis (e.g., SEQ. ID. Nos. 20 and 22) and a nucleic acidencoding an HCV protein derived from a hepatitis virus that infectshumans (e.g., SEQ. ID. No. 2). The nucleic acids present in saidcompositions can be in C is (e.g., operably joined in frame) or in Trans(e.g., on separate expression constructs altogether). By one approach,an individual in need of a medicament that inhibits HCV infection,reduces HCV viral titer, inhibits HCV replication, treats HCV infectionor that promotes an immune response to an HCV protein is identified andsaid individual is provided a medicament comprising a nucleic acidencoding an HBcAg antigen (e.g., SEQ. ID. Nos. 20 and 22) and a nucleicacid encoding an HCV antigen, such as codon-optimized NS3/4A (e.g., SEQ.ID. NO.: 1), or codon-optimized NS5A (e.g., SEQ. ID. No. 8).

Alternatively, an immunogenic composition comprising an HBcAgpolypeptide (e.g., SEQ. ID. Nos. 21 and 23), or a fragment thereof, andan HCV antigen described herein (e.g., codon-optimized NS3/4A in SEQ.ID. No. 1) are used to prepare a medicament for the inhibition of HCVinfection, the reduction of HCV viral titer, the inhibition of HCVreplication, the treatment of HCV infection or for the generation of animmune response to an HCV protein.

Some embodiments concern methods of inhibiting HBV infection, reducingHBV viral titer, inhibiting HBV replication, treating HBV infection orpromoting an immune response specific for an HBV protein. By oneapproach, an immunogenic composition comprising a nucleic acid encodingHBcAg (e.g., a human codon-optimized nucleic acid encoding a HBcAgderived from an avian hepatitis, such as a hepatitis that infects stork(e.g., SEQ. ID. No. 20) or heron (e.g., SEQ. ID. No. 22)) and anisolated nucleic acid encoding an HBV antigen described herein (e.g., ahuman codon-optimized nucleic acid encoding a HBcAg (e.g., SEQ. ID. No.10), a HBV surface antigen, a HBV e antigen (e.g., SEQ. ID. Nos. 12 and14), a HBV polymerase antigen, or a HBV x antigen derived from ahepatitis that infects humans) are used to prepare a medicament for theinhibition of HBV infection, the reduction of HBV viral titer, theinhibition of HBV replication, the treatment of HBV infection or for thegeneration of an immune response to an HBV protein. That is, preferredcompositions comprise, consist essentially of, or consist of an HBcAgderived from an avian hepatitis and a nucleic acid encoding an HBVprotein derived from a hepatitis virus that infects humans. The nucleicacids present in said compositions can be in C is (e.g., operably joinedin frame) or in Trans (e.g., on separate expression constructsaltogether). By one approach, an individual in need of a medicament thatinhibits HBV infection, reduces HBV viral titer, inhibits HBVreplication, treats HBV infection or that promotes an immune response toan HBV protein is identified and said individual is provided amedicament comprising a nucleic acid encoding an avian HBcAg (e.g., SEQ.ID. No. 20 and 22) and an HBV antigen, such as codon-optimized HBVantigen (e.g., codon-optimized HBeAg (e.g., SEQ. ID. NO.: 11)).

Alternatively, an immunogenic composition comprising an HBcAgpolypeptide, or a fragment thereof, and an HBV antigen described hereinare used to prepare a medicament for the inhibition of HBV infection,the reduction of HBV viral titer, the inhibition of HBV replication, thetreatment of HBV infection or for the generation of an immune responseto an HBV protein.

Some embodiments concern methods of ameliorating a birch allergy,reducing sensitivity to a birch allergen, or reducing IgE antibodylevels specific to birch. By one approach, an immunogenic compositioncomprising a nucleic acid encoding HBcAg (e.g., a human codon-optimizednucleic acid encoding a HBcAg derived from an avian hepatitis, such as ahepatitis that infects stork (e.g., SEQ. ID. No. 20) or heron (e.g.,SEQ. ID. No. 22)) and an isolated nucleic acid encoding a birch antigen(e.g., SEQ. ID. No 18) are used to prepare a medicament for theameliorating a birch allergy, reducing sensitivity to a birch allergy,or reducing IgE antibody levels specific to birch. That is, preferredcompositions comprise, consist essentially of, or consist of an HBcAgderived from an avian hepatitis and a nucleic acid encoding an birchantigen derived. The nucleic acids present in said compositions can bein C is (e.g., operably joined in frame) or in Trans (e.g., on separateexpression constructs altogether). By one approach, an individual inneed of a medicament that ameliorates a birch allergy, reducessensitivity to a birch allergen, or reduces IgE antibody levels specificto birch is identified and said individual is provided a medicamentcomprising a nucleic acid encoding an avian HBcAg (e.g., SEQ. ID. No. 20and 22) and a birch antigen, such as codon-optimized birch antigen(e.g., SEQ. ID. NO.: 18).

Alternatively, an immunogenic composition comprising an HBcAgpolypeptide, or a fragment thereof, and an birch antigen describedherein are used to prepare a medicament for ameliorating a birchallergy, reducing sensitivity to a birch allergen, or reducing IgEantibody levels specific to birch antigen.

The effective dose and method of administration of a particularformulation can vary based on the individual patient and the type andstage of the disease, as well as other factors known to those of skillin the art. Therapeutic efficacy and toxicity can be determined bystandard pharmaceutical procedures in cell cultures or experimentalanimals, e.g., ED50 (the dose therapeutically effective in 50% of thepopulation). The data obtained from cell culture assays and animalstudies can be used to formulate a range of dosage for human use. Thedosage lies preferably within a range of circulating concentrations thatinclude the ED50 with no toxicity. The dosage varies within this rangedepending upon the type of adjuvant derivative and antigen, the dosageform employed, the sensitivity of the patient, and the route ofadministration.

In certain embodiments an adjuvant is included within the administeredcomposition. For instance, a pharmacologic agent can be added to acomposition described herein as needed to increase or aid its effect. Inanother example, an immunological agent that increases the antigenicresponse can be utilized with a device described herein. For instance,U.S. Pat. No. 6,680,059 (which is hereby incorporated in its entirety byreference) describes the use of vaccines containing ribavirin as anadjuvant to the vaccine. However, an adjuvant may refer to any materialthat has the ability to enhance or facilitate an immune response or toincrease or aid the effect of a therapeutic agent. Non-limiting exampleof adjuvants include interleukin-2 (IL2), interleukin-12 (IL12),interleukin-15 (IL15), interleukin-21 (IL21), interleukin-28b (IL28b),galactosyl transferase, a toll-like receptor (TLR), ribavirin, alum,CpGs, and an oil. Also, as described above, in some embodiments, thecomposition includes an isolated nucleic acid, or constructs comprisingsaid nucleic acids, encoding a protein that is an adjuvant, such as IL2,IL12, IL15, IL21, IL28b, galactosyl transferase, a TLR, and the like. Incertain aspects, the isolated nucleic acid encoding the protein which isan adjuvant may be in the same construct encoding HBcAg and/or theheterologous protein. In some aspects, methods of administering theimmunogenic composition comprise administering an adjuvant beforeadministering the immunogenic composition.

In some embodiments, the method includes administering an immunogeniccomposition that comprises an isolated nucleic that encodes HBcAg, or afragment thereof, and separately administering an isolated nucleic acidthat encodes a heterologous protein (e.g., SEQ. ID. No. 8). When theisolated nucleic acid encoding HBcAg and the isolated nucleic acidencoding the heterologous protein are administered separately, theisolated nucleic acid encoding HBcAg may, in some embodiments, may beadministered before the isolated nucleic acid encoding heterologousprotein. Alternatively, the isolated nucleic acid encoding heterologousprotein may, in some embodiments, be administered before the isolatednucleic acid encoding HBcAg.

Other embodiments of the methods disclosed herein include administeringa composition including both HBcAg and the heterologous protein. In someembodiments, the method includes administering an immunogeniccomposition that includes an admixture of an isolated nucleic acidencoding HBcAg and an isolated nucleic acid encoding the heterologousprotein. In certain embodiments, the method includes administering animmunogenic composition that includes an admixture of an isolatednucleic acid encoding the HBcAg and an isolated nucleic acid encodingthe heterologous protein.

Various routes of administration may be used for the methods describedherein. In some embodiments, the immunogenic composition is administeredparenterally (e.g., intramuscularly, intraperitoneally, subcutaneously,or intravenously to a mammal subject). In a preferred embodiment, theimmunogenic compositions are administered intramuscularly, dermally, orsubcutaneously. The methods may also include applying electricalstimulation, which can enhance the administration of the immunogeniccompositions. As an example, electroporation may be included in thepresent methods disclosed herein. Electroporation includes applyingelectrical stimulation to improve the permeability of cells to theadministered composition. Examples of electroporation techniques aredisclosed in U.S. Pat. Nos. 6,610,044 and 5,273,525, the disclosures ofboth of these references are hereby incorporated by reference in theirentireties.

The concentration of the nucleic acid or protein in the immunogeniccomposition to be administered can vary from about 0.1 ng/ml to about 50mg/ml. In some aspects, the concentration of the immunogenic compositionadministered (e.g., a suitable dose of nucleic acid or protein foradministration) is between about 10 ng/ml to 25 mg/ml. In still otheraspects, the concentration is between 100 ng/ml to 10 mg/ml. In someaspects, the suitable dose of nucleic acid or protein for administrationis greater than or equal to or less than about 100 ng/ml, 150 ng/ml, 200ng/ml, 250 ng/ml, 300 ng/ml, 350 ng/ml, 400 ng/ml, 450 ng/ml, 500 ng/ml,550 ng/ml, 600 ng/ml, 650 ng/ml, 700 ng/ml, 750 ng/ml, 800 ng/ml, 850ng/ml, 900 ng/ml, 950 ng/ml, 1 μg/ml, 2 μg/ml, 3 μg/ml, 4 μg/ml, 5μg/ml, 6 μg/ml, 7 μg/ml, 8 μg/ml, 9 μg/ml, 10 μg/ml, 11 μg/ml, 12 μg/ml,13 μg/ml, 14 μg/ml, 15 μg/ml, 16 μg/ml, 17 μg/ml, 18 μg/ml, 19 μg/ml, 20μg/ml, 21 μg/ml, 22 μg/ml, 23 μg/ml, 24 μg/ml, 25 μg/ml, 26 μg/ml, 27μg/ml, 28 μg/ml, 29 μg/ml, 30 μg/ml, 31 μg/ml, 32 μg/ml, 33 μg/ml, 34μg/ml, 35 μg/ml, 36 μg/ml, 37 μg/ml, 38 μg/ml, 39 μg/ml, 40 μg/ml, 41μg/ml, 42 μg/ml, 43 μg/ml, 44 μg/ml, 45 μg/ml, 46 μg/ml, 47 μg/ml, 48μg/ml, 49 μg/ml, 50 μg/ml, 55 μg/ml, 60 μg/ml, 65 μg/ml, 70 μg/ml, 75μg/ml, 80 μg/ml, 85 μg/ml, 90 μg/ml, 95 μg/ml, 100 μg/ml, 150 μg/ml, 200μg/ml, 250 μg/ml, 300 μg/ml, 350 μg/ml, 400 μg/ml, 450 μg/ml, 500 μg/ml,550 μg/ml, 600 μg/ml, 650 μg/ml, 700 μg/ml, 750 μg/ml, 800 μg/ml, 850μg/ml, 900 μg/ml, 950 μg/ml, 1.0 mg/ml, 1.1 mg/ml, 1.2 mg/ml, 1.3 mg/ml,1.4 mg/ml, 1.5 mg/ml, 1.6 mg/ml, 1.7 mg/ml, 1.8 mg/ml, 1.9 mg/ml, 2.0mg/ml, 2.1 mg/ml, 2.2 mg/ml, 2.3 mg/ml, 2.4 mg/ml, 2.5 mg/ml, 2.6 mg/ml,2.7 mg/ml, 2.8 mg/ml, 2.9 mg/ml, 3.0 mg/ml, 3.1 mg/ml, 3.2 mg/ml, 3.3mg/ml, 3.4 mg/ml, 3.5 mg/ml, 3.6 mg/ml, 3.7 mg/ml, 3.8 mg/ml, 3.9 mg/ml,4.0 mg/ml, 4.1 mg/ml, 4.2 mg/ml, 4.3 mg/ml, 4.4 mg/ml, 4.5 mg/ml, 4.6mg/ml, 4.7 mg/ml, 4.8 mg/ml, 4.9 mg/ml, 5.0 mg/ml, 5.1 mg/ml, 5.2 mg/ml,5.3 mg/ml, 5.4 mg/ml, 5.5 mg/ml, 5.6 mg/ml, 5.7 mg/ml, 5.8 mg/ml, 5.9mg/ml, 6.0 mg/ml, 6.1 mg/ml, 6.2 mg/ml, 6.3 mg/ml, 6.4 mg/ml, 6.5 mg/ml,6.6 mg/ml, 6.7 mg/ml, 6.8 mg/ml, 6.9 mg/ml, 7.0 mg/ml, 7.1 mg/ml, 7.2mg/ml, 7.3 mg/ml, 7.4 mg/ml, 7.5 mg/ml, 7.6 mg/ml, 7.7 mg/ml, 7.8 mg/ml,7.9 mg/ml, 8.0 mg/ml, 8.1 mg/ml, 8.2 mg/ml, 8.3 mg/ml, 8.4 mg/ml, 8.5mg/ml, 8.6 mg/ml, 8.7 mg/ml, 8.8 mg/ml, 8.9 mg/ml, 9.0 mg/ml, 9.1 mg/ml,9.2 mg/ml, 9.3 mg/ml, 9.4 mg/ml, 9.5 mg/ml, 9.6 mg/ml, 9.7 mg/ml, 9.8mg/ml, 9.9 mg/ml, 10.0 mg/ml, 11 mg/ml, 12 mg/ml, 13 mg/ml, 14 mg/ml, 15mg/ml, 16 mg/ml, 17 mg/ml, 18 mg/ml, 19 mg/ml, 20 mg/ml, 21 mg/ml, 22mg/ml, 23 mg/ml, 24 mg/ml, 25 mg/ml, 26 mg/ml, 27 mg/ml, 28 mg/ml, 29mg/ml, 30 mg/ml, 31 mg/ml, 32 mg/ml, 33 mg/ml, 34 mg/ml, 35 mg/ml, 36mg/ml, 37 mg/ml, 38 mg/ml, 39 mg/ml, 40 mg/ml, 41 mg/ml, 42 mg/ml, 43mg/ml, 44 mg/ml, 45 mg/ml, 46 mg/ml, 47 mg/ml, 48 mg/ml, 49 mg/ml, 50mg/ml, or within a range defined by, and including, any two of thesevalues.

The amount of nucleic acid or protein administered using the methodsdescribed herein can vary from about 1 ng to 10 g. In some aspects, theamount of nucleic acid or protein contained administered is less thangreater than or equal to about 1 ng, 5 ng, 10 ng, 20 ng, 30 ng, 40 ng,50 ng, 60 ng, 70 ng, 80 ng, 90 ng, 100 ng, 150 ng, 200 ng, 250 ng, 300ng, 350 ng, 400 ng, 500 ng, 600 ng, 700 ng, 800 ng, 900 ng, 1 μg1 μg, 2μg, 3 μg, 4 μg, 5 μg, 6 μg, 7 μg, 8 μg, 9 μg, 10 μg, 11 μg, 12 μg, 13μg, 14 μg, 15 μg, 16 μg, 17 μg, 18 μg, 19 μg, 20 μg, 21 μg, 22 μg, 23μg, 24 μg, 25 μg, 26 μg, 27 μg, 28 μg, 29 μg, 30 μg, 31 μg, 32 μg, 33μg, 34 μg, 35 μg, 36 μg, 37 μg, 38 μg, 39 μg, 40 μg, 41 μg, 42 μg, 43μg, 44 μg, 45 μg, 46 μg, 47 μg, 48 μg, 49 μg, 50 μg, 55 μg, 60 μg, 65μg, 70 μg, 75 μg, 80 μg, 85 μg, 90 μg, 95 μg, 100 μg, 105 μg, 110 μg,115 μg, 120 μg, 125 μg, 130 μg, 135 μg, 140 μg, 145 μg 150 μg, 155 μg,160 μg, 165 μg, 170 μg, 175 μg, 180 μg, 185 μg, 190 μg, 195 μg 200 μg,205 μg, 210 μg, 215 μg, 220 μg, 225 μg, 230 μg, 235 μg, 240 μg, 245 μg250 μg, 255 μg, 260 μg, 265 μg, 270 μg, 275 μg, 280 μg, 285 μg, 290 μg,295 μg, 300 μg, 305 μg, 310 μg, 315 μg, 320 μg, 325 μg, 330 μg, 335 μg,340 μg, 345 μg 350 μg, 355 μg, 360 μg, 365 μg, 370 μg, 375 μg, 380 μg,385 μg, 390 μg, 395 μg 400 μg, 405 μg, 410 μg, 415 μg, 420 μg, 425 μg,430 μg, 435 μg, 440 μg, 445 μg 450 μg, 455 μg, 460 μg, 465 μg, 470 μg,475 μg, 480 μg, 485 μg, 490 μg, 495 μg 500 μg, 505 μg, 510 μg, 515 μg,520 μg, 525 μg, 530 μg, 535 μg, 540 μg, 545 μg 550 μg, 555 μg, 560 μg,565 μg, 570 μg, 575 μg, 580 μg, 585 μg, 590 μg, 595 μg 600 μg, 605 μg,610 μg, 615 μg, 620 μg, 625 μg, 630 μg, 635 μg, 640 μg, 645 μg 650 μg,655 μg, 660 μg, 665 μg, 670 μg, 675 μg, 680 μg, 685 μg, 690 μg, 695 μg,700 μg, 705 μg, 710 μg, 715 μg, 720 μg, 725 μg, 730 μg, 735 μg, 740 μg,745 μg 750 μg, 755 μg, 760 μg, 765 μg, 770 μg, 775 μg, 780 μg, 785 μg,790 μg, 795 μg, 800 μg, 805 μg, 810 μg, 815 μg, 820 μg, 825 μg, 830 μg,835 μg, 840 μg, 845 μg 850 μg, 855 μg, 860 μg, 865 μg, 870 μg, 875 μg,880 μg, 885 μg, 890 μg, 895 μg 900 μg, 905 μg, 910 μg, 915 μg, 920 μg,925 μg, 930 μg, 935 μg, 940 μg, 945 μg 950 μg, 955 μg, 960 μg, 965 μg,970 μg, 975 μg, 980 μg, 985 μg, 990 μg, 995 μg, 1.0 mg, 1.1 mg, 1.2 mg,1.3 mg, 1.4 mg, 1.5 mg, 1.6 mg, 1.7 mg, 1.8 mg, 1.9 mg, 2.0 mg, 2.1 mg,2.2 mg, 2.3 mg, 2.4 mg, 2.5 mg, 2.6 mg, 2.7 mg, 2.8 mg, 2.9 mg, 3.0 mg,3.1 mg, 3.2 mg, 3.3 mg, 3.4 mg, 3.5 mg, 3.6 mg, 3.7 mg, 3.8 mg, 3.9 mg,4.0 mg, 4.1 mg, 4.2 mg, 4.3 mg, 4.4 mg, 4.5 mg, 4.6 mg, 4.7 mg, 4.8 mg,4.9 mg, 5.0 mg, 5.1 mg, 5.2 mg, 5.3 mg, 5.4 mg, 5.5 mg, 5.6 mg, 5.7 mg,5.8 mg, 5.9 mg, 6.0 mg, 6.1 mg, 6.2 mg, 6.3 mg, 6.4 mg, 6.5 mg, 6.6 mg,6.7 mg, 6.8 mg, 6.9 mg, 7.0 mg, 7.1 mg, 7.2 mg, 7.3 mg, 7.4 mg, 7.5 mg,7.6 mg, 7.7 mg, 7.8 mg, 7.9 mg, 8.0 mg, 8.1 mg, 8.2 mg, 8.3 mg, 8.4 mg,8.5 mg, 8.6 mg, 8.7 mg, 8.8 mg, 8.9 mg, 9.0 mg, 9.1 mg, 9.2 mg, 9.3 mg,9.4 mg, 9.5 mg, 9.6 mg, 9.7 mg, 9.8 mg, 9.9 mg, 10.0 mg, 11 mg, 12 mg,13 mg, 14 mg, 15 mg, 16 mg, 17 mg, 18 mg, 19 mg, 20 mg, 21 mg, 22 mg, 23mg, 24 mg, 25 mg, 26 mg, 27 mg, 28 mg, 29 mg, 30 mg, 31 mg, 32 mg, 33mg, 34 mg, 35 mg, 36 mg, 37 mg, 38 mg, 39 mg, 40 mg, 41 mg, 42 mg, 43mg, 44 mg, 45 mg, 46 mg, 47 mg, 48 mg, 49 mg, 50 mg, 55 mg, 60 mg, 65mg, 70 mg, 75 mg, 80 mg, 85 mg, 90 mg, 95 mg, 100 mg, 150 mg, 200 mg,250 mg, 300 mg, 350 mg, 400 mg, 450 mg, 500 mg, 550 mg, 600 mg, 650 mg,700 mg, 750 mg, 800 mg, 850 mg, 900 mg, 950 mg, 1 g, 2 g, 3 g, 4 g, 5 g,6 g, 7 g, 8 g, 9 g, 10 g or within a range defined by, and including,any two of these values.

The following examples are given to illustrate various embodiments ofthe present invention in the field of DNA immunization, which can bedelivered to a subject in need of an immune response to the antigencontained therein. It is to be understood that the following examplesare not comprehensive or exhaustive of the many types of embodimentswhich can be prepared in accordance with the present invention.

Example 1

The NS3/4A sequence was amplified from the serum of an HCV-infectedpatient (HCV genotype 1a) using the Polymerase Chain Reaction (PCR).Total RNA was extracted from serum, and cDNA synthesis and PCR wereperformed according to standard protocols (Chen M et al., J. Med. Virol.43:223-226 (1995)). The cDNA synthesis was initiated using the antisenseprimer “NS4KR” (5′-CCG TCT AGA TCA GCA CTC TTC CAT TTC ATC-3′ (SEQ. ID.NO. 98)). From this cDNA, a 2079 base pair DNA fragment of HCV,corresponding to amino acids 1007 to 1711, which encompasses the NS3 andNS4A genes, was amplified. A high fidelity polymerase (Expand HighFidelity PCR, Boehringer-Mannheim, Mannheim, Germany) was used with the“NS3KF” primer (5′-CCT GAA TTC ATG GCG CCT ATC ACG GCC TAT-3′ (SEQ. ID.NO. 99) and the NS4KR primer. The NS3KF primer contained a EcoRIrestriction enzyme cleavage site and a start codon and the primer NS4KRcontained a XbaI restriction enzyme cleavage site and a stop codon.

The amplified fragment was then sequenced (SEQ. ID. NO. 100). Sequencecomparison analysis revealed that the gene fragment was amplified from aviral strain of genotype 1a. A computerized BLAST search against theGenbank database using the NCBI website revealed that the closest HCVhomologue was 93% identical in nucleotide sequence.

The amplified DNA fragment was then digested with EcoRI and XbaI, andwas inserted into a pcDNA3.1/His plasmid (Invitrogen) digested with thesame enzymes. The NS3/4A-pcDNA3.1 plasmid was then digested with EcoRIand Xba I and the insert was purified using the QiaQuick kit (Qiagen,Hamburg, Germany) and was ligated to a EcoRI/Xba I digested pVAX vector(Invitrogen) so as to generate the NS3/4A-pVAX plasmid.

The NS3 truncated mutant was obtained by deleting NS4A sequence from theNS3/4A DNA. Accordingly, the NS3 gene sequence of NS3/4A-pVAX was PCRamplified using the primers NS3KF and 3′NotI (5′-CCA CGC GGC CGC GAC GACCTA CAG-3′ (SEQ. ID. NO.: 101)) containing EcoRI and Not I restrictionsites, respectively. The NS3 fragment (1850 bp) was then ligated to aEcoRI and Not I digested pVAX plasmid to generate the NS3-pVAX vector.Plasmids were grown in BL21 E. coli cells. The plasmids were sequencedand were verified by restriction cleavage and the results were as to beexpected based on the original sequence.

Example 2

To assess the ability of HBcAg DNA constructs to prime CTLs, the nucleicacid of SEQ ID NO:10 is cloned into the pVAX1 expression vector(Invitrogen, Carlsbad, Calif.) to create HBcAg-pVAX1.

Plasmids are grown in BL21 E. coli cells, and sequenced for accuracy.Plasmid DNA used for in vivo vaccination is purified using Qiagen DNApurification columns, according to the manufacturer's instructions(Qiagen GmbH, Hilden, FRG).

Groups of eight to ten C57/BL6 mice are primed with HBcAg-pVAX1 intramuscularly (i.m.). For i.m. delivery, mice are immunized by needleinjections of 100 μg plasmid DNA given intramuscularly to the tibialisanterior (TA) muscle. 5 days prior to DNA immunization, mice areinjected intramuscularly with 50 μl per TA muscle of 0.01 mM cardiotoxin(Latoxan) in 0.9% sterile saline. The mice are boosted with a secondinjection of 100 μg plasmid DNA four weeks subsequent to the first DNAimmunization. Each injection dose contains 100 μg of plasmid DNA.Immunizations are performed at weeks 0 and 4.

The presence of CTLs specific for SEQ ID NO:10 is assayed using astandard ⁵¹Cr-release assay. Briefly, spleen cells are harvested frommice 14 days after the initial immunization or the booster immunization.Chromium release assays are performed as described in Lazdina, et al.(2003) J. Gen. Virol. 84:1-8, herein expressly incorporated by referencein its entirety. Single cell suspensions are prepared. 25×10⁶splenocytes are restimulated with 25×10⁶ syngenic irradiated (20 Gy)splenocytes pulsed with 0.05 μM peptide, as previously described.Sandberg et al. (2000) J. Immunol. 165:25-33, herein expresslyincorporated by reference in its entirety. Restimulation cultures areset in 12 ml complete RPMI medium (Gibco). After 5 days, effector cellsare harvested and washed twice. RMA-S target cells (Karre et al. (1986)Nature 319:675-678) are pulsed with 50 μM peptide for 90 min at 5% CO₂and 37° C. Serial dilutions of effector cells are incubated with 5×10³⁵¹chromium-labeled peptide pulsed RMA-S target cells in a final volumeof 200 μl per well in 96-well plates. After a 4 hour incubation at 5%CO₂ and 37° C., 100 μl of supernatant is collected and the radioactivityis determined using a γ counter. The percentage of specific release iscalculated according to the formula: (Experimental release−spontaneousrelease/total release−spontaneous release)×100.

Example 3

The expression of the HBcAg and NS3/4a proteins from plasmids wereanalyzed by an in vitro transcription and translation assay. Eachsequence was cloned into pVAX1 expression vector (Invitrogen, Carlsbad,Calif.).

The following constructs were studied: (1) codon-optimized NS3/4A (SEQ.ID. No. 2); (2) codon-optimized HBcAg; (3) NS3/4A-HBcAg (SEQ. ID. No.73); (4) mutant NS3/4A-HBcAg (SEQ. ID. No. 75); (5) N53-NS4A/Bjunction-N54-HBcAg (SEQ. ID. No. 77) (6) N53-NS4A/B junction-NS4-NS4A/Bjunction-HBcAg (SEQ. ID. No. 79); and (5-11) NS3/4A-NS4A/Bjunction-HBcAg fragments (SEQ. ID Nos. 81, 83, 85, 87 and 89,respectively) (hereinafter Constructs 1-11, respectively).

FIGS. 2 a-b show the results of gel electrophoresis using 10% Tris-HClSDS gel after 24 hours of exposure. The results confirm that constructsencoding cleavage sites were cleaved to form multiple, distinctproteins. For example, Construct 4 exhibits 2 sharp bands associatedwith two portions of the encoded polypeptide that are separated by acleavage site. In contrast, nucleic acids lacking cleavage sites, suchas Construct 2, exhibit only a single sharp band.

Example 4

Constructs 1 and 4, as discussed in Example 3, were tested in mousemodels to assay the ability to induce and immune response. Plasmids weregrown in BL21 E. coli cells, and sequenced for accuracy. Plasmid DNAused for in vivo vaccination was purified using Qiagen DNA purificationcolumns, according to the manufacturer's instructions (Qiagen GmbH,Hilden, FRG). The concentration of the resulting plasmid DNA wasdetermined spectrophotometrically (Dynaquant, Pharmacia Biotech,Uppsala, Sweden) and the purified DNA was dissolved in sterile phosphatebuffered saline (PBS) at a concentration of 1 mg/ml.

Two types of mice were tested, HLA-A2 transgenic mice (HHD) and HCVNS3/4A+HLA-A2 transgenic mice (H3). The HCV NS3/4A+HLA-A2 transgenicmouse model is a preferred animal model for therapeutic vaccinationbecause it provides a partly human immune system that is dysfunctionaldue to a persistent presence of a viral antigen. Accordingly, this modelis representative of chronic HCV infection in humans.

Mice were intra muscularly (i.m.) immunized with 50 μg of Construct 1 or4 at 0 and 4 weeks. Meanwhile, four other mice groups wereco-administered 50 μg of IL-12 or IL-21 along with Construct 1 or 4 at 0and 4 weeks. Mice were sacrificed at week 6 and spleens harvested andanalyzed for HCV-specific IFNγ production by ELISpot as described inAhlen G, Soderholm J, Tjelle T E, et al. “In vivo ElectroporationEnhances the Immunogenicity of Hepatitis C Virus Nonstructural3/4A DNAby Increased Local DNA Uptake, Protein Expression, Inflammation, andInfiltration of CD3+ cells,” J. Immunol. (2007), which is herebyincorporated by reference in its entirety. Table 1 provided below showsa list of restricted peptides in the transgenic mice whose expressionwas detected using ELISpot.

IDENTIFIER RESTRICTED SEQUENCE SEQ. ID. NO. TP-5 GLLGCIITSL 90 TP-6TGSPITYSTY 91 TP-7 KLVALGVNAV 92 TP-9 CINGVCWTV 93 TP-10 LLCPAGHAV 94TP-11 ATMGFGAYM 95 TP-12 YLVAYQATV 96 TP-13 TLHGPTPLL 97

ELISpot results are shown in FIGS. 3 a-e and 4 a-e for the HHD and H3animal models, respectively. More specifically, FIG. 3 a-c shows theimmune response from the administration of codon-optimized NS3/4A(Construct 1), codon-optimized NS3/4A coadministered with IL-12, andmutant NS3/4A-HBcAg (Construct 4), respectively, when administered toHHD mice. The adjuvant activity of HBcAg is demonstrated by theincreased immune response of mice receiving Construct 4 relative to bothConstruct 1 and Construct 1 co-administered with IL-12. FIGS. 4 a-c showthe immune response from the administration of codon-optimized NS3/4A(Construct 1), codon-optimized NS3/4A coadministered with IL-12, andmutant NS3/4A-HBcAg (Construct 4), respectively, when administered to H3mice. These results further demonstrate the adjuvant activity of HBcAg.

To further improve the immune response, mutant NS3/4A-HBcAg wasco-administered with either IL-12 or IL-21 to HHD and H3 mice. FIGS. 3d-e show results in the HHD mouse model, and demonstrate the immuneresponse is further increased by the addition of IL-12 or IL-21,relative to mutant NS3/4A-HBcAg administered alone (i.e., as shown inFIG. 3 c). The results show IL-12 produced generally a greater immuneresponse compared to IL-21. Finally, FIGS. 4 d-e show the results in theH3 mouse model. Again, both IL-12 and IL-21 improved the immune responseof mutant NS3/4A-HBcAg relative the administration of mutantNS3/4A-HBcAg alone (i.e., as shown in FIG. 4 c). Most interestingly,IL-21 produced a generally greater immune response in H3 mouse comparedto IL-12.

Examples 4-13

To further evaluate the adjuvant activity of HBcAg, both HHD and H3transgenic mice are instramuscularly administered compositions havingconstructs encoding HBcAg and isolated constructs encoding an antigen.To prepare each construct, each sequence is independently cloned into aseparate pVAX1 expression vector (Invitrogen, Carlsbad, Calif.). Theplasmids are prepared generally using the same techniques as disclosedin Example 2.

Compositions are prepared by admixing a vector encoding codon-optimizedHBcAg and a vector encoding an antigen in sterile phosphate bufferedsaline (PBS) at a concentration of 1 mg/ml. 50 μg of this mixture isadministered intramuscularly to HHD and H3 mice using the sametechniques and analyzed using ELISpot as described in Example 3. Theseresults are compared to mice receiving antigen but withoutco-administered HBcAg.

Table 2 below lists the specific nucleic acids inserted into vectors andcontained in the admixtures administered for Examples 4-13. Thus, forexample, Example 4 includes the administration of a vector encodingcodon-optimized stork HBcAg, and a vector encoding codon-optimizedNS3/4A.

EXAMPLE HBcAg (SEQ. ID. No.) ANTIGEN (SEQ. ID. NO.) 4 20 2 5 22 2 6 20 87 22 8 8 20 10 9 22 10 10 20 12 11 22 12 12 20 16 13 22 16 14 20 18 1522 18

It will be shown that the presence of HBcAg in the composition promotesa more robust immune response to the antigen in the subject, as comparedto administration of a composition of antigen that excludes effectiveamounts of HBcAg.

EXAMPLES 14-43

Additional experiments to study the immunogenic properties of isolatednucleic acids encoding HBcAg joined to a heterologous protein can beperformed. The procedures are generally the same as those described inExample 4, which briefly includes inserting the sequence into the pVAX1plasmid and administering a composition of the plasmid to HHD and H3transgenic mice. The immune response is determined using ELISpot andcompared to the immune response resulting from administering plasmidsencoding the antigen without HBcAg. The nucleic acids used in Examples14-43 are shown below in Table 3.

NUCLEIC ACID EXAMPLE (SEQ. ID. NO.) 14 24 15 26 16 28 17 30 18 32 19 3420 36 21 38 22 40 23 42 24 44 25 46 26 48 27 50 28 52 29 54 30 56 31 5832 60 33 62 34 64 35 66 36 68 37 81 38 83 49 85 40 87 41 89 42 103 43105

It will be shown that the compositions having HBcAg joined to an antigenpromote a more robust immune response to the antigen in the subject, ascompared to administration of a composition of antigen that excludeseffective amounts of HBcAg joined to the antigen.

1. An expression construct comprising an isolated nucleic acid thatcomprises: a nucleotide sequence encoding a fusion protein of ahepatitis B virus core antigen (HBcAg) from an avian hepatitis virusjoined to a hepatitis C virus (HCV) antigen, wherein said HCV antigencomprises NS3/4A and, wherein said nucleotide sequence is codonoptimized for expression in humans.
 2. The expression construct of claim1, wherein said HCV antigen further comprises NS5A.
 3. The expressionconstruct of claim 1, wherein one or more protein cleavage sites areencoded between the HBcAg portion and the NS3/4A antigen portion of saidfusion protein.
 4. The expression construct of claim 3, wherein said oneor more protein cleavage sites are included at a non-naturally occurringposition with respect to the HBcAg.
 5. The expression construct of claim3, wherein said one or more protein cleavage sites are NS3 proteasecleavage sites.
 6. The expression construct of claim 1, wherein saidHBcAg is from a hepatitis virus that infects a stork.
 7. The expressionconstruct of claim 1, wherein said HBcAg is from a hepatitis virus thatinfects a heron.
 8. An immunogenic composition comprising: an isolatednucleic acid that comprises a nucleotide sequence encoding a fusionprotein of a hepatitis B virus core antigen (HBcAg) from an avianhepatitis virus joined to a hepatitis C virus (HCV) antigen, whereinsaid nucleotide sequence is codon optimized for expression in humans andsaid HCV antigen comprises NS3/4A; and an excipient.
 9. The immunogeniccomposition of claim 8, further comprising an adjuvant.
 10. Theimmunogenic composition of claim 9, wherein said adjuvant is selectedfrom the group consisting of: interleukin 2 (IL-2), interleukin 12(IL-12), interleukin 15 (IL-15), and interleukin 21 (IL-21).
 11. Theimmunogenic composition of claim 8, wherein said HCV antigen furthercomprises NS5A.
 12. The immunogenic composition of claim 8, wherein oneor more protein cleavage sites are encoded between the HBcAg portion andthe NS3/4A antigen portion of said fusion protein.
 13. The immunogeniccomposition of claim 8, wherein said one or more protein cleavage sitesare included at a non-naturally occurring position with respect to theHBcAg.
 14. The immunogenic composition of claim 8, wherein said one ormore protein cleavage sites are NS3 protease cleavage sites.
 15. Theimmunogenic composition of claim 8, wherein said HBcAg is from ahepatitis virus that infects a stork.
 16. The immunogenic composition ofclaim 8, wherein said HBcAg is from a hepatitis virus that infects aheron.
 17. A method of inducing an immune response to a hepatitis Cvirus (HCV) antigen in a subject comprising: providing the expressionconstruct of claim 1 to a subject; and evaluating the immune response ofsaid subject to said HCV antigen.
 18. The method of claim 17, whereinthe subject is infected with hepatitis B virus (HBV) or the subject thathas antibodies specific for HBV.
 19. The method of claim 17, whereinsaid subject is chronically infected with HCV.
 20. A method of inducingan immune response to a hepatitis C virus (HCV) antigen in a subjectcomprising: providing the immunogenic composition of claim 8 to asubject; and evaluating the immune response of said subject to said HCVantigen.
 21. The method of claim 20, wherein the subject is infectedwith hepatitis B virus (HBV) or the subject that has antibodies specificfor HBV.
 22. The method of claim 20, wherein said subject is chronicallyinfected with HCV.